Cholinesterase Research Outreach Project (CROP): measuring cholinesterase activity and pesticide use in an agricultural community

Morbidity Profile and Cholinesterase Levels among Sprayers in Selected Tea Plantations in South India

BACKGROUND

The tea plantation industry is composed of a complex chain of workers whose functions often overlap. There has been an extensive use of pesticides in this sector, and in the long term, these can have detrimental effects on the chemical sprayers working in the tea plantations.

AIMS

To assess the morbidities related to pesticide toxicity and document the most recent plasma cholinesterase levels among the pesticide sprayers working in selected tea plantations in South India.

METHODS

A cross-sectional study was conducted among 290 chemical sprayers in selected tea plantations in South India after approval from the Institutional Ethics Committee and permission from the plantations. A structured interview schedule was administered by face-to-face interview with the selected sample. The blood cholinesterase detection done at the Estate Hospital was documented by the interviewer.

RESULTS

The mean age of the participants was 45.6 ± 8.5 years and all of them were males. About 35.2% of the participants had reported at least one symptom of organophosphorus toxicity. The most common symptom was headache (21.7%) followed by itching of the eyes (20%) and watering of the eyes (16.2%). The blood cholinesterase values were normal in most of the sprayers in the study and only four (1.4%) sprayers had values less than the reference range. There was a significant association between the duration of work, method of spraying, and the blood cholinesterase levels indicating that greater duration of exposure and more direct contact with the chemical raise the cholinesterase levels significantly.

CONCLUSION

The symptoms of pesticide toxicity were reported among the sprayers. The blood cholinesterase levels were normal for most of them.

Research Engagement Changes Attitudes and Behaviours towards Agrichemical Safety in Australian Farmers

There is limited research that evaluates the effect of farmer involvement in agrichemical exposure surveillance on their attitudes and behaviour towards pesticide handling and use of personal protective equipment. This limited follow-up study aimed to (i) evaluate attitudes/behaviours towards the use of personal protective equipment (PPE) among farmers who participated in the In-Field Personalised Cholinesterase Assessment Project (PCAP) (2016/17); and (ii) qualitatively assess the effect of monthly presentation of acetylcholinesterase (AChE) testing results on farmer agrichemical safety practices and behaviours prior to, and following participation in PCAP. This study surveyed 42 farming men and women, asking questions about agrichemical usage and hygiene practices. The majority of surveyed farmers’ self-apply agrichemicals on their farm (97.6%), with 81% reporting that involvement in PCAP research changed the way they handled Organophosphates (OPs)—a widely used insecticide in agriculture. By enabling people to think critically about their exposure, there was a 66% increase in frequency of respirator usage post-PCAP. Following this, participants were invited to take part in one-on-one interviews to further discuss their involvement in PCAP. Many responses were positive, with participants stating they were more aware and cautious of their own practices. This study determined that research participation and point-of-care testing and education can result in effective engagement of farmers and farm workers, increase health literacy and change farming practice—highlighting the importance of an interactive, participatory model in order to bring about change, to reduce possible pesticide exposures.

A Pest to Mental Health? Exploring the Link between Exposure to Agrichemicals in Farmers and Mental Health

The current literature acknowledges that occupational exposures can adversely affect mental health. This review seeks to elucidate the current understanding of the effect of agrichemical exposure on mental health in the agricultural sector, including low-dose, chronic pesticide exposure. This scoping review adopted a snowballing and saturation approach. The review highlights inconsistencies in linking poor mental health and pesticide use. While some studies specifically showed that both high- and low-dose pesticide exposure were associated with poor mental health, consistent and rigorous research methods are lacking. The review also proposes terms to delineate exposure types described in the literature. The review outcomes direct efforts to protect the health, wellbeing and safety of farming communities across the globe.

Enzymatic changes in orchard workers with occupational exposure to pesticides

Organophosphates (OP) and carbamates, frequently used pesticides, can cause a variety of adverse health effects, ranging from simple irritation of the skin and eyes to more severe effects. The aim of this study was to evaluate the association between chronic occupational pesticide exposure and changes in serum activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma glutamyl transferase (GGT), alkaline phosphatase (ALP), acetylcholinesterase (AChE) and creatine phosphokinase (CPK) in orchard workers. In the study, 47 peach orchard workers were included, at the age from 19 to 60 years, with monthly exposure to pesticides from 5 to 20 days and 1 to 35 working years. The control group consisted of 40 healthy age-matched men, without exposure to pesticides. All orchard workers kept to safety precautions. 68% of workers reported some physical signs and symptoms. A significantly decreased AChE activity was detected in 10.6% of orchard workers and increased CPK activity in 40.4%. Very weak negative correlation was detected between AChE and ALP activities (r = -0.34, p = 0.001) and between AChE and CPK activities (r = -0.25, p = 0.02). No correlation was found between the serum AChE and day of monthly exposure, as well as years of exposure. The results have shown that orchard workers with decreased AChE activity and increased CPK activity should be monitored as workers with an increased risk for severe pesticide poisoning. These findings suggest that chronic occupational exposure to pesticides elicit mild toxic effects, as well as biochemical changes of unknown long-term consequences. Keywords: Toxic effects; Carbamates pesticide, Organophosphate pesticide, Serum enzymes, Orchard workers, Occupational exposure

Cholinesterase research outreach project (CROP): point of care cholinesterase measurement in an Australian agricultural community

BACKGROUND

Australian farmers are routinely exposed to a wide variety of agrichemicals, including herbicides and insecticides. Organophosphate (OP) insecticides are widely used for agricultural production, horticulture and animal husbandry practices. Symptoms of OP toxicity are the results of inhibition of the enzyme acetylcholinesterase (AChE) which is found in many types of conducting tissue in human bodies such as nerve and muscle, central and peripheral tissues, motor and sensory fibres. Cholinesterase can be measured in red blood cells/erythrocytes (AChE) and plasma (PChE). This study aims to explore integration of AChE monitoring into routine health checks for those at risk and also to examine any association between AChE activity and agrichemical use in a Victorian farming community in Australia.

METHODS

This was a prospective cohort study, where farmers and non-famers were compared on the levels of AChE at four time points of baseline, 3-4 weeks, 6-weeks and at 9-weeks. Study participants (N = 55) were residents from South West Victoria, aged between 18 and 75 years, spoke English, and had not had a previous known acute chemical accident. A total of 41 farming (had been farming for more than 5 years) and a convenience sample of 14 non-farming individuals met the inclusion criteria. Testing of AChE was repeated for all participants with a maximum of three times over 10 weeks.

RESULTS

The integration of AChE monitoring was very well accepted by all participants. There was no significant difference in average AChE activity between farming and non-farming participants (one-way ANOVA p > 0.05) in this study. There was no significant difference between personal use of agricultural chemicals on farm and the levels of AChE at baseline (measurement 1) or any of the follow up periods (p > 0.05). However, the mean activity of AChE was significantly lower within follow up periods [F (2.633, 139.539) = 14.967, p < 0.001]. There was a significant reduction of AChE between the follow up at 3-weeks and 6-weeks period (p = 0.015).

CONCLUSIONS

The routine monitoring of AChE may allow for early recognition of chronic low-level exposure to OPs when they are used by farmers, provided a reasonable estimate of baseline AChE is available. This work provides an evidence for recommending the integration of AChE monitoring into point of care (POC) procedures in rural health clinics and quantifying pesticide exposure and personal protection both on the farm and in the home. Farmer engagement is crucial to the successful integration of AChE monitoring into rural health clinics in Australia.

TRIAL REGISTRATION

ACTRN12613001256763 .

Effects of Organophosphorus Pesticides on Cardiorespiratory Parameters among the Farmers

INTRODUCTION

Indiscriminate use and improper handling of synthetic pesticides in agriculture have resulted in serious problems such as asthma, wheeze and chronic bronchitis among the farmers. Though number of studies have been done on pesticide exposure and its effect on cardiorespiratory parameters in Northern India, only few studies were done in Southern India, thus this study was chosen.

AIM

To find the cardiorespiratory changes in farm workers exposed to organophosphorus pesticides.

MATERIALS AND METHODS

Peak Expiratory Flow Rate (PEFR), blood pressure, pulse rate were measured among 35 farm workers of Palayam and Naduveerpattu village of Cuddalore district and 35 age, sex, BMI matched controls were taken from urban area and the same parameters were measured in both groups from 10 am-12 am in the morning. History of use of personal protective equipments like face mask, eye mask, special clothes, shoes, hat, history of respiratory symptoms and hygienic work practices was also obtained from the farmers. Chi-square test was used to analyse the qualitative data. All values were expressed as Mean±SD. Students unpaired t-test was used to compare PEFR between two groups and to compare the duration of exposure and PEFR using GRAPH PAD PRISM. The p<0.05 was considered to be statistically significant.

RESULTS

There was a significant decrease in PEFR among the farmers (p<0.001) compared to the controls. On comparing the duration of exposure of pesticide and the PEFR values by unpaired Students t-test, there was a significant difference with p-value of 0.03. Blood Pressure did not show any significant difference between the two groups. But the pulse rate was significantly decreased among the farmers (p<0.001) which could be due to their regular physical activity. About 71% of the farmers used personal protective equipments.

CONCLUSION

Thus, chronic exposure to organophosphorus pesticides has an impact on PEFR among the farmers.

Risk Factors of Pesticide Poisoning and Pesticide Users' Cholinesterase Levels in Cotton Production Areas: Glazoué and Savè Townships, in Central Republic of Benin

OBJECTIVE

To assess the degree of poisoning in farmers using the erythrocyte acetylcholinesterase (AChE) test before and after the exposure to pesticides in townships in central Benin (Glazoué and Savè) and to identify the associated risk factors.

METHODS

Using a cross-sectional study design, we recruited 264 farm pesticide sprayers, who have been working for at least 5 years. They completed a questionnaire and underwent the AChE test using the Test-mate Model 400 device (EQM Research Inc.) with a photometric sensor, based on the works of Ellman.

RESULTS

Organophosphate/pyrethroids were the most common pesticides used by at least 72.96% of the farmworkers. We observed an inhibition of AChE between pre-exposure and post-exposure (P = .002) for 60.61% of the farmworkers. Among them, 11.88% displayed more than 20% AChE inhibition.

CONCLUSIONS

Pesticide poisoning is a reality, and AChE monitoring is urgently needed for farmworker surveillance.