Upland cotton, Gossypium hirsutum L., is a natural source of fiber and a major row crop in the US with an estimated $7 billion raw product value in 2019. However, it is extremely sensitive to the broadleaf herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). With the evolution of herbicide-resistant weeds compounded by off-target spray damage on conventional cotton varieties outside the transgenic Enlist technology (Dow Agrosciences) of herbicide-tolerant cotton varieties (Dow Agrosciences), there is a need to identify and develop novel sources of herbicide tolerance gene for upland cotton genetic improvement. Cotton chromosome substitution (CS) lines carry introgressions from other cultivated and wild allotetraploid Gossypium species that could be sources of novel and exotic alleles for herbicide tolerance. A total of 50 CS lines of G. barbadense L. (CS-B), G. tomentosum Nuttal ex Seeman (CS-T), and G. mustelinum Meers ex Watt (CS-M), in the genetic background of G. hirsutum L. Texas Marker-1 (TM-1) were screened for resistance to a field-recommended rate (1.12 kg ae ha-1) of 2,4-D in the greenhouse. Seven CS lines, CS-T04-15, CS-B12, CS-B15sh, CS-T04, CS-B22sh, CS-T07, and CS-B04-15 with the lowest injury were evaluated for tolerance at four and seven weeks after seedling emergence under field conditions. Progeny tests conducted in the greenhouse validated 2,4-D tolerance of CS-B15sh, showing 41% lower injury than TM-1. Novel variants of CS-T04-15 and CS-T07 were identified with complete tolerance to the herbicide but are segregating. Uptake and translocation of 14C-labeled 2,4-D indicated that reduced translocation of 2,4-D may be the 2,4-D tolerance mechanism in CS-T04-15 and CS-T07, while gene(s) associated with metabolism and reduced auxin transport appeared associated with the 2,4-D tolerance in CS-B15sh. Transcriptome analysis revealed differential expression of genes in 2,4-D-treated CS-B15sh and TM-1 with several components of the 2,4-D/auxin response pathway, including ubiquitin E3 ligase, PB1|AUX/IAA, ARF transcription factors, and F box proteins of the SCFTIR1/AFB complex being up-regulated. Functional annotation of differentially expressed genes revealed down-regulation of auxin transport, suggesting a potential linkage with tolerance mechanism involving altered movement of 2,4-D in CS-B15sh. The selected highly tolerant cotton CS lines will need to be confirmed further using molecular assays.

Agriculture is a valuable economic resource in western Canada, but for decades farmers have focused on intensive production practices while ignoring the long-term health and maintenance of the land. In recent years, the use of conservation agricultural techniques has been encouraged in an effort to conserve prairie landscape while sustaining cropland productivity. Sustainable agricultural practices that promote soil and water conservation and benefit wildlife and prairie biodiversity include conservation tillage and planting of winter cereal crops. Many species of wild birds nest in the ground cover provided by minimum tillage and fall seeded cropland in the spring. Although habitat quality in conservation areas is superior for birds, there is potential for eggs of ground nesting birds to be exposed to herbicides during spring weed control operations. Herbicides commonly used on the prairies to control weed growth in conservational systems include 2,4-D and Buctril-M®. Since the subtlethal effects of exposure to these herbicides may include DNA damage and immunomodulation, the overall goal of this study was to assess whether <i>in ovo</i> exposure to the herbicides 2,4-D and Buctril-M® adversely affects genetic material and/or immune system function in newly hatched domestic chickens (<i>Gallus gallus</i>) and ducks (<i>Anas platyrhynchos</i>), as surrogates for wild bird species.<p>Study design attempted to reproduce actual field exposures by use of an agricultural field spray simulator to apply formulated herbicides (as opposed to pure active ingredients) at recommended crop application rates. In three separate experiments, fertile chicken eggs were sprayed with 2,4-D ester formulation or with Buctril-M® formulation, and fertile duck eggs were sprayed with 2,4-D ester formulation, during either an early (embryonic day 6) or late (embryonic day 15 for chickens or embryonic day 21 for ducks) stage of incubation. Genotoxicity and immune system function were evaluated in the hatchlings as the main toxicological endpoints to assess potential subtle effects from herbicide exposure, but additional measures of general health and development were also evaluated. Two endpoints were used to assess subtle changes to genetic integrity. The comet assay was used to detect structural damage (strand breaks) in avian lymphocyte DNA, as an index of acute genotoxic effects. Flow cytometry was used to examine potential clastogenic effects of the herbicides, by determining if chromosomal changes resulted in variability in the DNA content of avian erythrocytes. Several endpoints were examined to evaluate potential exposure-induced effects on the immune system. Immunopathological assessment of chicks and ducklings included differential lymphocyte counts, as well as immune organ weights and histopathology. The cell-mediated and humoral immune responses in hatchlings were assessed using the delayed-type hypersensitivity test and measurement of systemic antibody production in response to immunization, respectively. Exposure of fertile chicken and duck eggs to Buctril-M® or 2,4-D had no effects on the biomarkers of genetic integrity in this study. Differences in herbicide treatment (high and low concentrations) and times of exposure (early and late incubation stages) did not translate into noticeable factor effects in final model analyses for any of the genotoxicity assay variables evaluated in newly hatched chickens exposed in ovo to 2,4-D. Similarly, comet assay outcomes in chicks exposed to Buctril-M® were not significantly associated with either herbicide treatment or time of exposure as fixed effect factors. Results of the comet assay using peripheral lymphocytes from ducklings provided evidence of potential primary genetic damage associated with the time of spray exposure in ovo. Comet tail DNA content was significantly associated (P = 0.0269) with exposure times, suggesting that ducks may be increasingly sensitive to spray exposure conditions at an early stage of embryological development. Effects of exposure timing were not attributable to herbicide treatment. Although 2,4-D exposure time was associated with DNA strand breakage in ducklings, there was no evidence of chromosomal damage. However, an association between the HPCV values (a measure of DNA content variability) and time of spray exposure was observed in the experiment where 21-day-old chickens were treated in ovo with Buctril-M®. The mean HPCV value for the early exposure group (E6) was significantly greater (P = 0.0210) than that of the group treated later in incubation (E15). However, Buctril-M® the concentration of herbicide did not have any influence on this outcome, and the reason for the difference between exposure times is uncertain, but may be attributed to stress associated with manipulations during spraying. An increase in HPCV, reflecting greater intercellular DNA variability, is indicative of increased incidence of chromosomal damage, which may be an effect of disturbance during early periods of incubation as a result of exposure conditions.<p>Among the panel of immunotoxicity tests conducted to evaluate the effects of <i>in ovo</i> exposure to 2,4-D and Buctril-M® on the developing avian immune system, only heterophil/ lymphocyte (H/L) ratios and relative immune organ weights were significantly associated with either herbicide treatment or time of spray exposure in all three experiments. In 21-day-old chicks exposed in ovo to 2,4-D, relative bursa weight was associated with the different herbicide treatments (P = 0.0006). Relative bursa weights were significantly lower in chicks in the low dose group, while the opposite effect was observed in the high dose chicks, compared with the controls. It is unlikely that the observed decrease in bursa weight in the low dose group is causally related to herbicide exposure because a consistent dose-response effect was not observed, but this outcome may be explained by a compensatory immune response. The relative spleen weights of newly hatched chickens exposed in ovo to Buctril-M® exhibited a significant association with herbicide treatment (P = 0.0137). Relative spleen weights for birds in the low dose treatment groups were significantly different than both the control (P = 0.0179) and high dose groups (P = 0.0125). However, there was no significant difference between high dose and control groups, and this outcome reduces the likelihood of a causal relationship between spleen weight and herbicide exposure. In the parallel experiment involving in ovo exposure to 2,4-D to ducklings, relative bursa weight was associated with time of spray exposure (P = 0.0434). Ducklings that hatched from eggs exposed to spray on day 6 of incubation exhibited greater mean relative bursa weights than the birds exposed to spray at a later incubation stage (E21). This result implies that spray exposure during earlier stages of development may result in conditions which affect the humoral immune response, if increased bursal weight is associated with increased B lymphocyte and antibody production. In the same experiment, mean H/L ratios in peripheral blood samples from 21-day-old ducklings were significantly different between the groups treated with the high concentration of 2,4-D and water (control) (P = 0.0395). Although ratios from the birds in the low dose groups were not significantly different from the control groups, changes in H/L ratio values demonstrate a dose dependent relationship with increasing herbicide exposure.<p>Residue analysis of chicken and duck eggs in this study measured transfer of herbicide through the shell and into the embryo 24 hours and up to 5 days (chickens only) after spraying. Mean 2,4-D residue concentrations were higher in both chicken and duck eggs from the high dose (10X) groups than in eggs exposed to the recommended field rate of herbicide application (1X). Embryo residue concentrations in the chicken eggs increased from the day following exposure to 5 days after spraying, in both low and high dose groups. This observation indicates that the risk of contaminant-induced adverse effects may continue to increase for at least several days after exposure, thereby influencing the concentration of herbicide to which the developing embryo is exposed.<p>On the Canadian prairies, wild bird eggs are potentially to be exposed to 2,4-D and Buctril-M® during various stages of embryonic development. The present study examined effects of herbicide exposure at two distinct times during incubation, and demonstrated the potential for subtle impacts on genetic integrity and the immune system. Results indicate that spray exposure during earlier stages of organogenesis may cause more significant adverse effects. Given the possible harmful consequences of the observed changes on the long-term health of wild birds, further research is needed in order to better characterize the risks of in ovo agrochemical exposure in prairie ecosystems.

Agriculture is a valuable economic resource in western Canada, but for decades farmers have focused on intensive production practices while ignoring the long-term health and maintenance of the land. In recent years, the use of conservation agricultural techniques has been encouraged in an effort to conserve prairie landscape while sustaining cropland productivity. Sustainable agricultural practices that promote soil and water conservation and benefit wildlife and prairie biodiversity include conservation tillage and planting of winter cereal crops. Many species of wild birds nest in the ground cover provided by minimum tillage and fall seeded cropland in the spring. Although habitat quality in conservation areas is superior for birds, there is potential for eggs of ground nesting birds to be exposed to herbicides during spring weed control operations. Herbicides commonly used on the prairies to control weed growth in conservational systems include 2,4-D and Buctril-M®. Since the subtlethal effects of exposure to these herbicides may include DNA damage and immunomodulation, the overall goal of this study was to assess whether <i>in ovo</i> exposure to the herbicides 2,4-D and Buctril-M® adversely affects genetic material and/or immune system function in newly hatched domestic chickens (<i>Gallus gallus</i>) and ducks (<i>Anas platyrhynchos</i>), as surrogates for wild bird species.<p>Study design attempted to reproduce actual field exposures by use of an agricultural field spray simulator to apply formulated herbicides (as opposed to pure active ingredients) at recommended crop application rates. In three separate experiments, fertile chicken eggs were sprayed with 2,4-D ester formulation or with Buctril-M® formulation, and fertile duck eggs were sprayed with 2,4-D ester formulation, during either an early (embryonic day 6) or late (embryonic day 15 for chickens or embryonic day 21 for ducks) stage of incubation. Genotoxicity and immune system function were evaluated in the hatchlings as the main toxicological endpoints to assess potential subtle effects from herbicide exposure, but additional measures of general health and development were also evaluated. Two endpoints were used to assess subtle changes to genetic integrity. The comet assay was used to detect structural damage (strand breaks) in avian lymphocyte DNA, as an index of acute genotoxic effects. Flow cytometry was used to examine potential clastogenic effects of the herbicides, by determining if chromosomal changes resulted in variability in the DNA content of avian erythrocytes. Several endpoints were examined to evaluate potential exposure-induced effects on the immune system. Immunopathological assessment of chicks and ducklings included differential lymphocyte counts, as well as immune organ weights and histopathology. The cell-mediated and humoral immune responses in hatchlings were assessed using the delayed-type hypersensitivity test and measurement of systemic antibody production in response to immunization, respectively. Exposure of fertile chicken and duck eggs to Buctril-M® or 2,4-D had no effects on the biomarkers of genetic integrity in this study. Differences in herbicide treatment (high and low concentrations) and times of exposure (early and late incubation stages) did not translate into noticeable factor effects in final model analyses for any of the genotoxicity assay variables evaluated in newly hatched chickens exposed in ovo to 2,4-D. Similarly, comet assay outcomes in chicks exposed to Buctril-M® were not significantly associated with either herbicide treatment or time of exposure as fixed effect factors. Results of the comet assay using peripheral lymphocytes from ducklings provided evidence of potential primary genetic damage associated with the time of spray exposure in ovo. Comet tail DNA content was significantly associated (P = 0.0269) with exposure times, suggesting that ducks may be increasingly sensitive to spray exposure conditions at an early stage of embryological development. Effects of exposure timing were not attributable to herbicide treatment. Although 2,4-D exposure time was associated with DNA strand breakage in ducklings, there was no evidence of chromosomal damage. However, an association between the HPCV values (a measure of DNA content variability) and time of spray exposure was observed in the experiment where 21-day-old chickens were treated in ovo with Buctril-M®. The mean HPCV value for the early exposure group (E6) was significantly greater (P = 0.0210) than that of the group treated later in incubation (E15). However, Buctril-M® the concentration of herbicide did not have any influence on this outcome, and the reason for the difference between exposure times is uncertain, but may be attributed to stress associated with manipulations during spraying. An increase in HPCV, reflecting greater intercellular DNA variability, is indicative of increased incidence of chromosomal damage, which may be an effect of disturbance during early periods of incubation as a result of exposure conditions.<p>Among the panel of immunotoxicity tests conducted to evaluate the effects of <i>in ovo</i> exposure to 2,4-D and Buctril-M® on the developing avian immune system, only heterophil/ lymphocyte (H/L) ratios and relative immune organ weights were significantly associated with either herbicide treatment or time of spray exposure in all three experiments. In 21-day-old chicks exposed in ovo to 2,4-D, relative bursa weight was associated with the different herbicide treatments (P = 0.0006). Relative bursa weights were significantly lower in chicks in the low dose group, while the opposite effect was observed in the high dose chicks, compared with the controls. It is unlikely that the observed decrease in bursa weight in the low dose group is causally related to herbicide exposure because a consistent dose-response effect was not observed, but this outcome may be explained by a compensatory immune response. The relative spleen weights of newly hatched chickens exposed in ovo to Buctril-M® exhibited a significant association with herbicide treatment (P = 0.0137). Relative spleen weights for birds in the low dose treatment groups were significantly different than both the control (P = 0.0179) and high dose groups (P = 0.0125). However, there was no significant difference between high dose and control groups, and this outcome reduces the likelihood of a causal relationship between spleen weight and herbicide exposure. In the parallel experiment involving in ovo exposure to 2,4-D to ducklings, relative bursa weight was associated with time of spray exposure (P = 0.0434). Ducklings that hatched from eggs exposed to spray on day 6 of incubation exhibited greater mean relative bursa weights than the birds exposed to spray at a later incubation stage (E21). This result implies that spray exposure during earlier stages of development may result in conditions which affect the humoral immune response, if increased bursal weight is associated with increased B lymphocyte and antibody production. In the same experiment, mean H/L ratios in peripheral blood samples from 21-day-old ducklings were significantly different between the groups treated with the high concentration of 2,4-D and water (control) (P = 0.0395). Although ratios from the birds in the low dose groups were not significantly different from the control groups, changes in H/L ratio values demonstrate a dose dependent relationship with increasing herbicide exposure.<p>Residue analysis of chicken and duck eggs in this study measured transfer of herbicide through the shell and into the embryo 24 hours and up to 5 days (chickens only) after spraying. Mean 2,4-D residue concentrations were higher in both chicken and duck eggs from the high dose (10X) groups than in eggs exposed to the recommended field rate of herbicide application (1X). Embryo residue concentrations in the chicken eggs increased from the day following exposure to 5 days after spraying, in both low and high dose groups. This observation indicates that the risk of contaminant-induced adverse effects may continue to increase for at least several days after exposure, thereby influencing the concentration of herbicide to which the developing embryo is exposed.<p>On the Canadian prairies, wild bird eggs are potentially to be exposed to 2,4-D and Buctril-M® during various stages of embryonic development. The present study examined effects of herbicide exposure at two distinct times during incubation, and demonstrated the potential for subtle impacts on genetic integrity and the immune system. Results indicate that spray exposure during earlier stages of organogenesis may cause more significant adverse effects. Given the possible harmful consequences of the observed changes on the long-term health of wild birds, further research is needed in order to better characterize the risks of in ovo agrochemical exposure in prairie ecosystems.

Horseweed (Conyza canadensis (L.) Cronq.) is prevalent in Kentucky and can be difficult to control. Research has shown multiple weed control methods to be more sustainable than relying on chemical control alone, so the use of multiple methods for horseweed management was examined in this study. The main objective was to determine best practice(s) to reduce horseweed prior to soybean [Glycine max (L.) Merr.]. Treatments included: fall-planted cover crop [CC; cereal rye (Secale cereale L.) or none], fall-applied herbicide (saflufenacil or none), and spring-applied herbicides (dicamba, 2,4-D ester, or none). We hypothesized horseweed densities would be reduced the most where all factors were combined. Saflufenacil suppressed horseweed densities from application through March, when densities increased due to a lack of competition from other winter weeds. Spring herbicides decreased horseweed densities until soybeans reached V1 in 2017, but in 2018 lost efficacy after CC termination. CC alone resulted in the longest horseweed suppression. The combination of spring herbicides and CC usually reduced horseweed densities to near zero between the CC termination and soybean planting. However, some low densities seen soon after soybean planting could be problematic. Further research must be conducted to determine the best integrated horseweed management system until soybean canopy closure.

New low volatile formulations of dicamba and 2,4-D are being developed to reduce injury to non-tolerant crops. Experiments were conducted comparing dicamba and 2,4-D volatility as affected by formulation, soil moisture content and soil texture. All formulations were applied to soil contained in greenhouse flats. After application greenhouse flats were then placed between a bio-indicator row of cotton and soybean. An open ended plastic dome covered the treated flats and crops for 48 hours prior to removal. Plant heights and yield of bio-indicator crops were unaffected by 2,4-D and dicamba volatility. Soil texture and moisture content did not significantly affect volatility. The greatest soybean crop injury was observed following application of the dimethylamine salt of dicamba and cotton injury was greatest following application of the ethylhexylester salt of 2,4-D. Volatility was generally reduced with new formulations of dicamba or 2,4-D; however, volatility was not completely eliminated.

This study was conducted to determine whether soybean productivity is affected by multiple, sublethal herbicide exposures. The effects of dicamba and 2,4-D on soybean (Glycine max) productivity was investigated at 17 site-years. Relative to a single exposure of dicamba at R1, an additional exposure at either V3 or R3 reduced yield up to 23%. Three or more applications did not further decrease yields relative to an R1&R3 exposure. For 2,4-D, a single application to V3, R1, R3, or R5 soybean did not affect grain yield. However, two exposures of 2,4-D occurring from V3 through R3 reduced yield 5 to 7%. Three or more applications of 2,4-D had no effect on yield relative to exposing soybean to 2,4-D twice between V3 and R3. Exposing soybean to multiple, sublethal rates of auxin herbicides can reduce yield relative to a single exposure and may be most deleterious from flowering to initial pod set.

[pt] Os agrotóxicos são utilizados principalmente nas lavouras e se dispersam no ambiente após aplicação, interferindo na qualidade do ar através da volatilização. Esta é influenciada pelas características do solo, características do agrotóxico, condições climáticas, cobertura vegetal e manejo agrícola. O objetivo deste trabalho foi caracterizar com parâmetros geotécnicos quatro solos de diferentes texturas que serviram de base para estudos preliminares de volatilização do herbicida 2,4-D. As propriedades de cada solo são importantes para identificar quais os parâmetros que mais influenciam na volatilização. Estudos foram feitos para desenvolver a metodologia de medição e pesquisar variações de manejo que resultem na menor perda por volatilização. A metodologia adotada utilizou microcosmos preenchidos com os solos previamente acondicionados, simulando a densidade natural. Após a aplicação do 2,4-D, os produtos voláteis foram captados por um processo de aspiração suave para uma resina XAD-2 capaz de sorver o herbicida. O sistema não é fechado para evitar distorções ambientais na temperatura, umidade e no vento, de forma a simular as condições naturais do ambiente. A extração do 2,4-D na resina foi feita pela extração com diclorometano e N-hexano (1:1) e sua quantificação foi realizada através da análise em cromatógrafo líquido com detector UV. A abordagem experimental mostrou que a metodologia utilizada permite grande perda pela ação dos ventos, requerendo um aperfeiçoamento metodológico. Os experimentos em campo foram conduzidos com quatro solos distintos do Rio de Janeiro em que a exposição do herbicida 2,4-D foi feita em duas sucessões distintas: uma com aplicação no início do dia – noite e a outra com aplicação no início da noite – dia, ambas com exposição de 24 horas. Nos cromatogramas das amostras com exposição ao sol foi observado, além do 2,4-D, outro composto em concentrações maiores, indicando possível metabólito. Foi observado que o efeito da umidade intersticial é preponderante sobre os outros parâmetros do solo, como o teor de matéria orgânica, e a volatilização foi maior nos experimentos que começaram no início da manhã comparados aos experimentos iniciados no final da tarde. A captação de voláteis somando os valores medidos na resina e nas espumas de poliuretano mostraram que a máxima volatilização foi no solo arenoso de Tinguá no turno da manhã, enquanto que o mínimo foi no turno da tarde para o mesmo solo. A redução de produtos volatilizados não é só um prejuízo na perda do produto, mas sobretudo uma redução da contaminação aérea, que poderá reduzir a exposição da flora e fauna, assim como a saúde humana. / [en] Pesticides are mainly used in crops and are dispersed into the environment, affecting the quality of the air by volatilization. This is influenced by the characteristics of the soil, pesticide properties, climate conditions, vegetation and agricultural management. It was performed geotechnical caracterization in four different soil textures to use them for preliminary studies of 2,4-D s volatilization. The properties of each soil are important to identify the parameters that most influence the volatilization. Studies have been done to develop the measurement methodology and to study management changes that result in reduced volatilization loss. In microcosm filled with soils simulating natural density was applied the herbicide 2,4-D in field concentrations. Volatilization products were captured by a gentle aspiration device with a XAD-2 resin. The system is not closed to prevent environmental distortions of temperature, umidity and wind, in order to simulate the natural conditions of the environment. The 2,4-D extraction of the resin was performed by extraction with dichloromethane and n-hexane (1:1) and quantification was performed by analyzing a liquid chromatograph with UV detector. The experimental methodology used needs to be improved to have a higher capture efficiency with wind loss reduction. The field experiments were conducted with four different soils of Rio de Janeiro state where exposure of 2,4-D herbicide was made in two separate sequences: one application earlier in the morning and the other application in the late evening, both with 24 hours exposure. In the chromatograms of all samples with sun exposure was observed, in addition to 2,4-D, another compound with higher concentrations indicating a possible photodegradation metabolite. It was observed that the effect of interstitial moisture is predominant over other soil parameters and volatilization was higher in the early morning experiments compared to the experiments started in the late afternoon. Considering the sum of XAD-2 resin and PUF, the maximum volatilization at 24 hour exposure was in the sandy soil of Tinguá during the morning shift, while the minimum was in the afternoon for the same soil. The reduction of volatilized products is not only a manner to enhance agronomic efficiency but mainly to reduce air pollution with a decrease of toxic effects on flora and fauna as well in human health.

Mixed Linkage Glucan (MLG, or (1,3;1,4)-ß-D glucan) is a component of cell walls for major cereal crops and is significant to food and beverage industries. To better understand genetic factors affecting MLG content in oats, this study investigates the presence of glucosidases likely to participate in MLG production. A glucosidase showing co-expression with CslF6—the primary gene responsible for MLG synthesis—could indicate a hand in MLG production by association. Reference genes for expression analysis as well as glucosidase candidates were first selected using in silico methods. In both cases, barley was used as model species because it has abundant public bioinformatic resources for in silico data mining, and it generates large amounts of MLG, like oats. Actin, malate dehydrogenase, and elongation factor 2, were validated in oat and barley as top reference genes. They were then used to compare the expression activity of the top glucosidase candidate gene, ßglux, with CslF6. ßglux was found to have increased activity with CslF6 during caryopsis development. It is a strong candidate for future transgenic experiments regarding its effect on MLG production.

A simple high pressure liquid chromatography procedure was used to determine 2,4-D and pronamide exposure in spraymen and their dermal absorption and excretion in guinea pigs. Results of dermal application of these herbicides to guinea pigs demonstrated a strong correlation between the applied dermal dose and the urinary residue excretion over the dosage range tested. As the dosage was increased, the urinary excretion of residues was also increased. However, the excretion of 2,4-D amine mixture following dermal treatment of guinea pigs was prolonged as compared to that of pronamide. Residue levels of these compounds were also determined to estimate skin contamination after sampling by filter pads attached to the clothing and arms of agricultural spraymen. Residues in the workers' urine before and after exposure were also determined. Average exposure values of 44.93 mg/hr/man for 2,40D and 0.83 mg/hr/man for pronamide were extrapolated from residue values obtained from analyzing the pads. Little correlation was found between the measured residues from exposed subjects and residues quantified in their urine samples.

Santrauka Humanitarinė intervencija ir jėgos nenaudojimo principas - daug diskusijų sukelianti tema. Atkreipti dėmesį į jėgos nenaudojimo principo ir humanitarinės intervencijos santykį skatina ne tik vyraujantis nuomonių skirtumas, bet ir palaipsniui vykstanti minėtų doktrinų modifikacija, kurią įtakoja valstybių praktika bei tarptautinėje arenoje vykstantys įvykiai. Darbe pateikiama trumpa humanitarinės intervencijos sampratų, kurias siūlo lietuvos ir užsienio autoriai, lyginamoji analizė. Taip pat aptariamas ir jėgos nenaudojimo principas. Antroje darbo dalyje glaustai pristatoma minėtų doktrinų istorinė raida. Trečiojoje darbo dalyje dėmėsys koncentruojamas į Jungtinių Tautų vaidmens, įgyvendinant jėgos nenaudojimo principą bei humanitarinės intervencijos doktriną, atskleidimui. Joje aptariama humanitarinės intervencijos ir jėgos nenudojimo principą įtvirtinančios Jungtinių Tautų Chartijos normos suderinamumo galimybė. Apžvelgiama Saugumo Tarybos ir Generalinės Asamblėjos kompetencija sankcionuojant jėgos naudojimą pagal Chartijos VII skyrių bei galimybė pasinaudoti šiuo mechanizmu įgyvendinant humanitarinę intervenciją. Šioje dalyje taip pat glaustai pristatoma ST praktika įgyvendinant humanitarinės intervencijos doktriną bei vieni iš svarbiausių atvejų, kuomet jėga humanitariniais tikslais buvo panaudota be ST sankcijos. Neapseita ir be Tarptautinio Teisingumo Teismo praktikos, kurioje sprendžiami jėgos nenaudojimo ir humanitarinės intervencijos klausimai, iškilę... [toliau žr. visą tekstą] / Humanitarian Intervention and the Non Use of Force Principle The doctrine of humanitarian intervention and the non use of force principle is the theme that causes a lot of discussions. But this is not the only reason that makes it interesting, there are also changes in both of them caused by states practice and events in international arena. In this work it is given short analysis of what are conceptions suggested by foreign and Lithuanian authors, what is humanitarian intervention. Also it is talked what is the principle of the non use of force. The second part of work is imposed for historical analysis of both doctrines. In the third part of work attention is concentrated in the role of the United Nations in implementation of the non use of force principle and humanitarian intervention. In this part it is talked about the possibility to match the norm of the United Nations Charter that firms the prohibition of the use of force in international relations and the doctrine of humanitarian intervention. Also, the competence of the United Nations Security Council and General assembly to authorize the use of force under the Chapter VII of the United Nations Charter and the possibility to use this mechanism for humanitarian purposes is viewed. This part of work also represents shortly the practice of Security Council when it authorized the use of force for humanitarian reasons. Also in this part there are some examples when the use of force for humanitarian purposes was not... [to full text]