Development and validation of an UPLC-MS/MS method for the determination of ionophoric and synthetic coccidiostats in vegetables.

In poultry farming, anticoccidial drugs are widely used as feed additives for the prevention and treatment of coccidiosis. Because coccidiostats and veterinary medicines, in general, are often poorly absorbed, manure from treated animals may contain high concentrations of these compounds. Experimental studies have shown that the uptake of veterinary medicines by plants from soil containing contaminated manure may occur. This leads to several questions regarding the impact on the environment, resistance problems, and public health and allergy issues. This work describes the development of a quantification method for coccidiostats in vegetables. Vegetables were spiked at 100 µg kg(-1) (dry weight) with coccidiostats (monensin, narasin, lasalocid A, salinomycin, diclazuril, and nicarbazin) in order to optimize the extraction and clean-up. Possible critical factors (e.g., extraction solvent) were statistically examined by linear regression with the use of Plackett-Burman and full factorial designs. Final extracts were analyzed with ultra-performance liquid chromatography tandem mass spectrometry operating in multiple-reaction monitoring mode. Both the synthetic and ionophoric coccidiostats could be determined in a single run with an analysis time of 5 min. The developed method was validated taking into account the requirements of the Commission Decision 2002/657/EC as a guideline. The method is regarded as applicable for its intended purposes with quantification limits between 0.30 and 2.98 µg kg(-1). This method could be used to establish possible maximum residue limits for coccidiostats in vegetables, as already exist for eggs, meat, and milk.

Pesticide knowledge and risk perception among adolescent Latino farmworkers.

A substantial proportion of the agricultural production in the U.S. is dependent on the labor of Latino farmworkers. While exact figures are not known, it is estimated that adolescents make up 7% of this valuable workforce. These young workers may be at increased risk for the toxic effects of environmental exposures encountered during their work. Furthermore, language barriers and health beliefs may influence the risk perceptions of this population. We conducted a cross-sectional survey of migrant adolescent farmworkers in 1998 to investigate their work practices, health beliefs, and pesticide knowledge. The large majority of the adolescents in our sample were from Mexico, and 36.3% spoke primarily indigenous languages. Many of the adolescents (64.7%) were traveling and working in the U.S. independent of their parents. Few of the adolescents reported having received pesticide training; however, 21.6% of the sample reported that their current work involved mixing and/or applying agricultural chemicals. The scores on the pesticide knowledge questionnaire were found to significantly predict self-reported use of protection for adolescent farmworkers. The results of this study point to a need for improved pesticide training in youth agricultural workers and specialized education efforts directed toward minorities who speak indigenous dialects. Special attention is merited toward adolescent farmworkers who report that their work includes mixing or applying agricultural chemicals. As the number of adolescent farmworkers increases in the U.S. and the characteristics of the migrant stream continue to change, culturally and developmentally appropriate instruments are needed to adequately assess the health beliefs and protective practices of this population.

The Oregon migrant farmworker community: an evolving model for participatory research.

Migrant farmworker communities present distinct challenges that require new approaches for community participation in research. In the State of Oregon an agency that advocates for the migrant farmworker community has collaborated successfully with university researchers to implement a research program directed to reducing pesticide exposures among the children of migrant farmworkers. The research process has included both qualitative research methods with members of the community and quantitative approaches to measure pesticide dust residues in homes, biomarkers of pesticide exposure, and effects on health. A committee of university and community stakeholders advises the research. Evaluative processes have been initiated to assess the effectiveness of the participatory model used in this project. The components of the preliminary process evaluation and results are presented. Evaluative data show that researchers and community members differ on perceptions of community involvement and the extent to which communication problems have been resolved between the two groups. Suggestions for improved community involvement and communication are given.

Symptoms of Gulf War veterans possibly exposed to organophosphate chemical warfare agents at Khamisiyah, Iraq.

During the 1991 Gulf War, some Allied troops were potentially exposed to sarin/cyclosarin as the result of the destruction of Iraqi munitions at Khamisiyah. To evaluate the prevalence of past and current symptoms known to be associated with exposure to these chemical warfare agents, the authors conducted a computer-assisted telephone survey of 2,918 U.S. Gulf War veterans. Veterans who had participated in or witnessed the demolition in 1991 were more likely to report historical or extant symptoms than were veterans from other military units. These results should be viewed cautiously because they are based on symptoms recalled nine years after the event without precise characterization of exposure. Nonetheless, the findings suggest that symptoms consistent with low-level sarin exposure may have initially occurred, and health effects may have persisted in the veterans who were nearest to the demolition activity. Further research is warranted.

Symptom factor analysis, clinical findings, and functional status in a population-based case control study of Gulf War unexplained illness.

Few epidemiological studies have been conducted that have incorporated clinical evaluations of Gulf War veterans with unexplained health symptoms and healthy controls. We conducted a mail survey of 2022 Gulf War veterans residing in the northwest United States and clinical examinations on a subset of 443 responders who seemed to have unexplained health symptoms or were healthy. Few clinical differences were found between cases and controls. The most frequent unexplained symptoms were cognitive/psychological, but significant overlap existed with musculoskeletal and fatigue symptoms. Over half of the veterans with unexplained musculoskeletal pain met the criteria for fibromyalgia, and a significant portion of the veterans with unexplained fatigue met the criteria for chronic fatigue syndrome. Similarities were found in the clinical interpretation of unexplained illness in this population and statistical factor analysis performed by this study group and others.