Pesticides are widely
used, resulting in continuing human exposure
with potential health impacts. Some exposures related to agricultural
works have been associated with neurological disorders. Since the
2000s, the hypothesis of the role of pesticides in the occurrence
of central nervous system (CNS) tumors has been better documented
in the literature. However, the etiology of childhood brain cancers
still remains largely unknown. The major objective of this work was
to assess the potential role of pesticide exposure as a risk factor
for CNS tumors based on questionnaires and statistical analysis of
information collected from patients hospitalized in the Neurosurgery
Department of the Habib Bourguiba Hospital Medium in Sfax, Tunisia,
during the period from January 1, 2022, to May 31, 2023. It also aimed
to develop a simple and rapid analytical method by the gas chromatography–mass
spectrometry technique for the research traces of pesticide metabolites
in some collected human brain tumor tissues in order to more emphasize
our hypothesis for such a correlation between pesticide exposure and
brain tumor development. Patients with a history of high-risk exposure
were selected to conduct further analysis. Chemometric methods were
adapted to discern intrinsic variation between pathological and control
groups and ascertain effective separation with the identification
of differentially expressed metabolites accountable for such variations.
Three samples revealed traces of pesticide metabolites that were mostly
detected at an early age. The histopathological diagnosis was medulloblastoma
for a 10-year-old child and high-grade gliomas for 27- and 35-year-old
adults. The bivariate analyses (odds ratio >1 and P value <5%) confirmed the great probability of developing cancer
by an exposure case. The Cox proportional hazards model revealed the
risk of carcinogenicity beyond the age of 50 as a long-term effect
of pesticide toxicity. Our study supports the correlation between
pesticide exposure and the risk of development of human brain tumors,
suggesting that preconception pesticide exposure, and possibly exposure
during pregnancy, is associated with an increased childhood brain
tumor risk. This hypothesis was enhanced in identifying traces of
metabolites from the carbamate insecticide class known for their neurotoxicity
and others from pyridazinone, organochlorines (OCs), triazole fungicide,
and N-nitroso compounds known for their carcinogenicity. The 2D-OXYBLOT
analysis confirmed the neurotoxicity effect of insecticides to induce
oxidative damage in CNS cells. Aldicarb was implicated in brain carcinogenicity
confirmed by the identification of oxime metabolites in a stress degradation
study. Revealing “aziridine” metabolites from the OC
class may better emphasize the theory of detecting traces of pesticide
metabolites at an early age. Overall, our findings lead to the recommendation
of limiting the residential use of pesticides and the support of public
health policies serving this objective that we need to be vigilant
in the p...