Biomonitoring of blood cholinesterases and acylpeptide hydrolase activities in rural inhabitants exposed to pesticides in the Coquimbo Region of Chile

Abstract

In Chile, agriculture is a relevant economic activity and is concomitant with the use of pesticides to improve the yields. Acute intoxications of agricultural workers occur with some frequency and they must be reported to the surveillance system of the Ministry of Health. However the impacts of chronic and environmental pesticide exposure have been less studied. Among pesticides frequently used in Chile for insects control are organophosphates (OP) and carbamates (CB). They are inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE). In this study we determined the pattern of both biomarkers activity in three populations with different type of chronic exposure to OP/CB: environmentally exposed (EE), occupationally exposed (OE) and a reference group (RG) without exposure. Besides this, we also measured the activity of acylpeptide hydrolase (APEH), an enzyme involved in relevant functions in the central synapses that is also expressed in erythrocytes and previously reported to be highly inhibited by some OP. A baseline measurement was done in both exposure groups and then a second measurement was done during the spraying season. The RG was measured only once at any time of the year. Our results indicate that people under chronic OP/CB exposure showed an adaptive response through an increase of basal BChE activity. During the spray season only BChE activity was decreased in the EE and OE groups (p<0.05 and p<0.01, respectively) and the higher magnitude of BChE inhibition was observed in the EE group. The analysis of the frequencies of inhibition above 30% (biological tolerance limit declared by Chilean legislation) indicated that BChE was most frequently inhibited in the EE group (53% of the individuals displayed inhibition) and AChE in the OE group (55% of the individuals displayed AChE inhibition). APEH activity showed the highest frequency of inhibition in the EE group independent of its magnitude (64%). Our results demonstrate that the rural population living nearby agricultural settings displays high levels of environmental exposure. APEH activity seems to be a sensitive biomarker for acute low-level exposure and its usefulness as a routine biomarker must to be explored in future studies. Systematic biomonitoring and health outcomes studies are necessary as well as obtaining the baseline for BChE and AChE activity levels with the aim to improve environmental and occupational health policies in Chile.

Health effects associated with occupational exposure to hand-arm or whole body vibration

“…However, these workers also are exposed to other factors such as pesticides and extreme temperatures. These exposures, along with vibration, may increase the risk of developing certain cancers, respiratory problems and neurodegenerative diseases (Suratman, Edwards,Babina 2015; Manyilizu et al 2016; Kachuri et al 2017; Bencko,Yan Li Foong 2017; Prado et al 2017; Piel et al 2017; Darcey et al 2018; Prudente et al 2018; Ramirez-Santana et al 2018; Anderson et al 2018). Studies need to be performed to determine how exposure to these various factors affect the risk of developing these vibration-induced illnesses.…”

“…Agricultural workers can be exposed to vibration and various pesticides. Pesticide exposure has been associated with the development of peripheral neuropathies, neurodegenerative disorders, and reproductive problems in workers (Suratman, Edwards,Babina 2015; Iavicoli et al 2017; Kab, Moisan,Elbaz 2017; Prudente et al 2018; Ramirez-Santana et al 2018; Anderson et al 2018). Understanding how these various exposures may contribute to the development of health problems is important determining the best actions to take to reduce exposure and the incidence of injury and disease.…”

Neuropsychiatric Disorders in Farmers Associated with Organophosphorus Pesticide Exposure in a Rural Village of Northwest México

“…However, we currently do not have an explanation of why we only found a reduction in the hemoglobin of exposed males, but not in exposed females. A decrease in AChE activity was observed in several studies after OP exposure [ 8 , 40 , 41 , 42 ]. In this study, the mean value of AChE enzymatic activity, the specific activity for the exposed participants was lower than the enzymatic activity of the nonexposed participants.…”

“…In this study, the mean value of AChE enzymatic activity, the specific activity for the exposed participants was lower than the enzymatic activity of the nonexposed participants. The decrease in AChE activity was thought to be related to the duration and frequency of pesticide exposure [ 42 ]. In this study, a relationship was found between AChE activity and the span of the exposure, using the number of years working in the field (~3 years average).…”

Pesticide Use and Serum Acetylcholinesterase Levels among Flower Farm Workers in Ethiopia—A Cross-Sectional Study

“…Another reason for the presence of similar abnormal SChE in spraying and non-spraying workers might be due to environmental pesticide exposure in their residences due to the drift of pesticides from both open field and greenhouse farms. We have no information about the overall environmental exposure, but in support of this argument, a study conducted in Chile and Thailand found no significant difference in cholinesterase levels among study participants who were occupationally exposed and those who were environmentally exposed [41,42].…”