Abstract
Purpose :
The use of pesticides is a common practice in agricultural-producing countries and represents one of the most significant industries globally. However, exposure to pesticides can adversely affect human health, leading to diseases such as cancer and neurodegenerative disorders. The visual system is connected to the central nervous system, which could give information about neuronal activity. For instance, contrast sensitivity is a cholinergic function, and it is associated with neuronal disorders. Therefore, the purpose of this study was to evaluate contrast sensitivity and neurocognitive function in individuals exposed to pesticides in Cundinamarca, Colombia.
Methods :
The study population included three groups: unexposed (n =23) individuals, environmentally exposed (n=22) and occupationally exposed (n=13). The daily exposure to agrochemicals was 7 to 9 hours a day for strawberry farm workers. Contrast sensitivity was analyzed at spatial frequencies of 0.5, 1.0, 3.0 6.0 12.0 cycles per degree. Neurocognitive functions, including visuospatial and visual memory, attention, inhibitory control, verbal fluency and sleep were also assessed. Analyses were performed using descriptive statistics and Spearman’s rank correlation was used between neuropsychological assessment and contrast sensitivity.
Results :
The study population included 58 subjects divided into three groups. The mean ages for unexposed, environmentally exposed and occupationally exposed subjects were 37.95±15.35, 41.47±16.99 and 37.70±13.79 respectively. Low spatial frequencies (0.5 and 1.0 cycles per degree) were reduced in both environmentally and occupationally exposed subjects (p<0.01). The occupationally exposed group showed significantly lower cognitive scores (p<0.025). Similar findings were observed in the exposed groups concerning sleep quality (P<0.002) and sleep disturbances (p<0.033). Interestingly, a correlation was found between fluency and some sleep characteristics with contrast sensitivity at 0.5 and 1.0 spatial frequencies (R=0.6; p<0.05).
Conclusions :
Contrast sensitivity was reduced at low spatial frequencies, and there were declines in several cognitive processes in individuals exposed to pesticides. These findings could serve as clinical markers for the early neurotoxic effects of pesticides.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.