Safety Practices, Neurological Symptoms, and Pesticide Poisoning

Factors affecting use of personal protective equipment and pesticide safety practices: A systematic review

An evidence-based understanding of factors influencing PPE use and pesticide safety practices has the benefit of facilitating the design of interventions to minimize exposure to pesticides and the promotion of the utilization of PPE and safety practices among agricultural pesticide handlers. The aim of this study, therefore, is to review the available literature on the use of PPE in agricultural pesticide handlers in world regions, and also the factors associated with the use of PPE and pesticide safety practices in farmers and farm workers. Full-text articles published on PubMed, Scopus, and ISI databases between 1999 and 2019 were reviewed and the scientific evidence was evaluated. One hundred and twenty-one articles were eligible for inclusion in this quantitative synthesis: 110 evaluated PPE use in agricultural pesticide handlers, and 23 focused on factors affecting PPE use and pesticide safety practices. Considerable evidence was found to show that the most basic PPE worn among pesticide handlers in all world regions was a long sleeve shirt (66.1%), long sleeve trousers (71.1%), and a hat (47.3%). The lowest basic PPE worn was an apron (8.6%), goggles (24.3%), gloves (40.5%), boots (42.3%), and mask (43.2%). The PPE worn (except for an apron) was proportionally higher in farmers than in farm workers. There is considerable evidence to suggest that the significant determinants associated with PPE use and pesticide safety practices are as follows: (1) demographic factors (i.e. education/literacy level, experience of illness, income); (2) farm structure factors (i.e. farm size); (3) behavioral and psychosocial factors (i.e. contact with pesticides, perceptions, attitudes, awareness, norms and beliefs); and (4) environmental factors (i.e. information about pesticides, access to extension services, training program, and farm organization). Therefore, there is a recognizable need for a life-long education program with training to change the perception and behavior of pesticide handlers sustainably.

Risk for Depressive Symptoms and Suicide Among U.S. Primary Farmers and Family Members: A Systematic Literature Review

Background: About 84% of the agriculture, fishing, and forestry occupational sector is comprised of farmers. This sector is at high risk for suicide in the United States. Recent disasters and trade upheavals may make farmers and their families more vulnerable to depression and suicide. This review focused on the risk for depression and suicide among United States’ primary farm operators and their families. Methods: A systematic search of the literature published between January 2000 and June 2019, using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) methodology was conducted. Results: A total of 30 articles met full inclusion criteria. Seventeen reports emanated from the midwest. Twenty studies used a cross-sectional design, primarily assessing a convenience sample or random stratified sample from a limited geographic area. We discovered only one intervention evaluation study. Depressive symptoms were assessed as part of the studies, but it was not the major focus. A variety of instruments measured depressive symptoms, with the Centers for Disease Control Epidemiologic Studies—Depression (CES-D) Scale used more frequently than other scales. Thirteen studies focused on the relationship between pesticide/chemical exposure and depression or suicide risk. Increased stress, poor physical health, compromised financial position, and previous injury were among the leading indicators of depression. Conclusion/Application to Practice: The limited number of studies that was discovered identified the need for more robust science where the risk for depression and suicide is the primary focus of the study and for intervention studies grounded in science. Occupational health providers should be vigilant about farm exposure and be aware of factors that may influence depressive symptoms of workers who operate farm establishments.

Organic solvent exposure and depressive symptoms among licensed pesticide applicators in the Agricultural Health Study

PURPOSE

Although organic solvents are often used in agricultural operations, neurotoxic effects of solvent exposure have not been extensively studied among farmers. The current analysis examined associations between questionnaire-based metrics of organic solvent exposure and depressive symptoms among farmers.

METHODS

Results from 692 male Agricultural Health Study participants were analyzed. Solvent type and exposure duration were assessed by questionnaire. An "ever-use" variable and years of use categories were constructed for exposure to gasoline, paint/lacquer thinner, petroleum distillates, and any solvent. Depressive symptoms were ascertained with the Center for Epidemiologic Studies Depression Scale (CES-D); scores were analyzed separately as continuous (0-60) and dichotomous (<16 versus ≥16) variables. Multivariate linear and logistic regression models were used to estimate crude and adjusted associations between measures of solvent exposure and CES-D score.

RESULTS

Forty-one percent of the sample reported some solvent exposure. The mean CES-D score was 6.5 (SD 6.4; median 5; range 0-44); 92% of the sample had a score below 16. After adjusting for covariates, statistically significant associations were observed between ever-use of any solvent, long duration of any solvent exposure, ever-use of gasoline, ever-use of petroleum distillates, and short duration of petroleum distillate exposure and continuous CES-D score (p < 0.05). Although nearly all associations were positive, fewer statistically significant associations were observed between metrics of solvent exposure and the dichotomized CES-D variable.

CONCLUSIONS

Solvent exposures were associated with depressive symptoms among farmers. Efforts to limit exposure to organic solvents may reduce the risk of depressive symptoms among farmers.

Pesticide poisoning and neurobehavioral function among farm workers in Jiangsu, People's Republic of China

Pesticides remain an integral part of agricultural activities worldwide. Although there have been a number of studies over the last two decades concerning the adverse effects of pesticide poisoning and chronic long term exposures on neurobehavioral function, the impact of recent pesticide poisoning and long term pesticide exposure on neurobehavioral function in Chinese farm workers has not been reported. China is the largest user of pesticides worldwide and figures suggest 53,300-123,000 Chinese people are poisoned every year. A case control study was conducted to examine the impact of recent pesticide poisoning on neurobehavioral function and the relationship between years worked in agriculture and lower performance on neurobehavioral tests. A total of 121 farm workers who self-reported recent pesticide poisonings within the previous 12 months (case group) and 80 farm workers who reported no pesticide poisoning in the previous 12 months (control group) were recruited from three areas of Jiangsu Province, China. The World Health Organization (WHO) recommended neurobehavioral core test battery (NCTB) was used to assess neurobehavioral functioning among cases and controls. Student's t tests and two-way covariance analysis (ANCOVA) were used to test for significant differences in the neurobehavioral test results between the groups. Scores on the Profile of Mood States (POMS) in the recently poisoned group were significantly higher for anger-hostility, depression-dejection, tension-anxiety and lower for vigor-activity compared to controls (p < .05). Digit span, digit symbol, Benton visual retention and pursuit aiming scores were all significantly lower among the recently poisoned group compared to the controls (p < .05). Two-way ANCOVA indicated significantly lower performance in correct pursuit aiming and higher error pursuit aiming amongst the recently poisoned group and those who had worked for more than 30 years in agriculture (p < .05). These findings provide important preliminary epidemiological evidence regarding the association between occupational pesticide exposure and neurobehavioral functioning in Chinese farm workers.

Longitudinal assessment of chlorpyrifos exposure and self-reported neurological symptoms in adolescent pesticide applicators

OBJECTIVES

Occupational exposure of organophosphorus pesticides, such as chlorpyrifos (CPF), in adolescents is of particular concern because of the potential vulnerability of the developing neurological system. The objectives of this study were to examine how neurological symptoms reported over the application season vary across time, whether these effects are reversible postapplication and if there are associations between CPF biomarkers and neurological symptoms in an adolescent study population.

SETTING

The longitudinal study was conducted in two agricultural districts of Menoufia Governorate, Egypt between April 2010 and January 2011.

PARTICIPANTS

Male adolescent participants, including CPF applicators (n=57) and non-applicators (n=38), were recruited.

PRIMARY AND SECONDARY OUTCOME MEASURES

Self-reported data for 25 neurological symptoms were collected at 32 time points over the 8-month period before, during and after the application season. Additionally, urine and blood samples were collected to measure urine trichloro-2-pyridinol (TCPy), a CPF-specific biomarker and blood cholinesterase activity.

RESULTS

Applicators and non-applicators report the highest numbers of symptoms during the application season, followed by a reduction in symptoms after the application ended. Applicators reported a greater percentage of neurological symptoms, relative to baseline, than non-applicators after accounting for potential covariates. Among the applicators, cumulative TCPy was positively and significantly associated with the average percentage of symptoms (B=4.56, 95% CI 3.29 to 5.84; p<0.001). Significant associations (p=0.03-0.07) between the change in butyrylcholinesterase activity from the preapplication to the postapplication season and several domains of neurological symptoms were also found, even after adjusting for potential covariates.

CONCLUSIONS

These observations demonstrate changes in the reporting of symptoms across the application season, showing an increase in symptom reporting during application and recovery following the end of pesticide application. These findings reinforce the growing concern regarding the neurotoxic health effects of CPF in adolescent applicators in developing countries and the need for developing and implementing intervention programmes.

Leaving family for work: ambivalence and mental health among Mexican migrant farmworker men

Men migrating to the United States from Mexico and Central America confront opposing family norms. They need to leave their families to gain family economic security; yet, leaving renders their families vulnerable. We examined the mental health implications of the opposing family norms inherent in migration using an ambivalence framework. We interviewed 60 Latino migrant farmworkers working in North Carolina. Most were from Mexico; each had left a wife and children in his country of origin. Analysis indicated that family ambivalence was common. Ambivalence was associated with anxiety symptoms (but not depression or alcohol dependence), especially among men who were unable to contact their families regularly. Results show the usefulness of the ambivalence framework, and suggest that the origins of poor migrant mental health may reside in circumstances preceding migration. Study recommendations include facilitating family contact by expanding access to telephones among migrant workers.

Structural equation modeling of the relationships between pesticide poisoning, depressive symptoms and safety behaviors among Colorado farm residents

PURPOSE

To use structural equation modeling (SEM) to test the theory that a past pesticide poisoning may act as a mediator in the relationship between depression and safety practices. Depression has been associated with pesticide poisoning and was more strongly associated with safety behaviors than workload, social support or health status of farm residents in a previously published report.

METHODS

A cross-sectional survey of farmers and their spouses was conducted in eight counties in northeastern Colorado. Depressive symptoms were assessed using the Center for Epidemiologic Studies-Depression (CES-D) scale. Exploratory and confirmatory factor analyses were used to identify symptoms most correlated with risk factors for depression and safety practices. SEM was used to examine theoretical causal models of the relationship between depression and poor health, financial difficulties, a history of pesticide poisoning, and safety practices.

RESULTS

Exploratory factor analysis identified three factors in the CES-D scale. The SEM showed that poor health, financial difficulties and a history of pesticide poisoning significantly explained the depressive symptoms. Models with an excellent fit for the safety behaviors resulted when modeling the probability that the pesticide poisoning preceded depression, but no fit was possible when reversing the direction and modeling depression preceding pesticide poisoning.

CONCLUSIONS

Specific depressive symptoms appeared to be significantly associated with primarily animal handling and farm machinery. The order of events, based on SEM results, was a pesticide poisoning preceding depressed mood in relation to safety behaviors.

Mortality among former Love Canal residents

BACKGROUND

The Love Canal is a rectangular 16-acre, 10-ft deep chemical waste landfill situated in a residential neighborhood in Niagara Falls, New York. This seriously contaminated site first came to public attention in 1978. No studies have examined mortality in the former residents of the Love Canal neighborhood (LC).

OBJECTIVE

The aim of this study was to describe the mortality experience of the former LC residents from the years 1979-1996.

METHODS

From 1978 to 1982, 6,181 former LC residents were interviewed. In 1996, 725 deaths from 1979-1996 were identified in this cohort, using state and national registries. We compared mortality rates with those of New York State (NYS) and Niagara County. Survival analysis examined risks by potential exposure to the landfill.

RESULTS

We were unable to demonstrate differences in all-cause mortality for either comparison population for 1979 1996. Relative to NYS, the standardized mortality ratio (SMR) was elevated [SMR = 1.39; 95% confidence interval (CI), 1.16-1.66] for death from acute myocardial infarction (AMI), but not relative to Niagara County. Death from external causes of injury was also elevated relative to both NYS and Niagara County, especially among women (SMR = 1.95; 95% CI, 1.25 2.90).

CONCLUSIONS

The role of exposure to the landfill in explaining these excess risks is not clear given limitations such as multiple comparisons, a qualitative exposure assessment, an incomplete cohort, and no data on deaths prior to 1978. Lack of elevation for AMI when compared with Niagara County but not NYS suggests possible regional differences. However, direct cardiotoxic or neurotoxic effects from landfill chemicals or indirect effects mediated by psychological stress cannot be ruled out. Revisiting the cohort in the future could reveal patterns that are not yet apparent.

Pesticide exposure, risk factors and health problems among cutflower farmers: a cross sectional study

This was a cross-sectional study which aimed to determine associations between hematologic indices such as red blood cell cholinesterase (RBC) and mean corpuscular volume (MCV), with illnesses related to pesticide exposure among cutflower farmers in La Trinidad, Benguet. One hundred two (102) randomly selected cutflower farmers underwent comprehensive, personal physical health and laboratory examinations and answered a questionnaire on work practices and illness. Majority were males (52%) and most belonged to the 20–35 age group (45%). Majority of exposed farmers were symptomatic, with most common complaints being headache (48%), easy fatigability (46.1%) and cough (40.2%). Analysis showed that RBC cholinesterase levels were positively associated with age (p = 0.02), and selling pesticide containers (p = 0.008). number of years of using pesticides (p = 0.022), use of contaminated cloth (p = 0.033), incorrect mixing of pesticides (p = 0.041), sex (p = 0.002) and illness due to pesticides (p = 0.005) were correlated with abnormal MCV. Significant associations were also found for hemoglobin, hematocrit, RBC, white blood cell (WBC) and platelet count. Predictors of RBC cholinesterase were years of pesticide use (p = 0.037) and abnormalities on health (p = 0.029). The findings of the study can be used for information dissemination and pesticide reduction programs for the cutflower farmers.

Risk factors to pesticide exposure and associated health symptoms among cut-flower farmers

The study looked into the risk factors associated with pesticide exposure among cut-flower farmers. A survey questionnaire was given to 102 respondents in Barangay Bahong in La Trinidad, the center of cut-flower production in the Philippines. Results showed that 32% were symptomatic or had experienced pesticide-related illnesses since their first use of pesticides. The majority of the pesticides used by the farmers were Categories Ib and II which are moderately or highly hazardous chemicals. Individuals with signs and symptoms most often centered on the eye, ear, nose and throat (EENT) (44 respondents reporting these symptoms) followed by general and neuralgic (16 respondents) and the integumentary (14 respondents). The most common general signs and symptoms manifested were weakness followed by fatigue and muscle pain then by chills and fever. The most common EENT manifestations were eye itchiness and blurring of vision. For neurological signs and symptoms, dizziness followed by headache was reported. Logistic regression showed that illnesses for the past 12 months were associated with certain risk factors such as farm use of pesticides, exposure to pesticide while applying it, respiratory inhalation of pesticide vapours and mists (p = 0.05). Moreover, those who re-entered a recently sprayed area were 20 times more likely to get ill during the past 12 months than those who did not. Those who used pesticide-contaminated pieces of fabric to wipe sweat off their faces were 2% more likely to get ill, and those who had spills on their bodies while applying pesticide were 26 times more likely to get ill. The study suggested that the risk factors to pesticide exposure should be considered in policy formulations for the cut-flower farmers in the country.