Exposure to pyrethroid and organophosphate insecticides in children – risk assessment for adverse effects on neuropsychological development and hormonal status
Epidemiological studies and animal experiments indicate the potential adverse effects of exposure to pyrethroid (PYR) and organophosphate (OP) insecticides on brain and sexual development in children, even at very low exposure levels. However, limited number of studies explored these potential risks during puberty, with inconsistent results and significant methodological limitations, such as insufficiently assessed exposure and cross-sectional study design. The main objective of the proposed research is to assess the risk of PYR and OP insecticide exposure to neuropsychological development and hormonal status in prepubertal and pubertal boys in a 2-year cohort study, while controlling for potential confounders, and using only non-invasive methods. Children’s exposure to PYR and OP insecticides will be assessed by biomonitoring (analysing urinary pesticide metabolites) in the 5th and 7th grades of elementary school, and by dietary exposure assessment – 24-hour dietary recall on five occasions during 2-year follow-up. In the 5th and 7th grades, neuropsychological development will be evaluated by testing attention, memory and simple psychomotor response speed, and by assessing the characteristics of child’s sleep and behaviour. Pubertal development will be evaluated by clinical examination (according to Tanner and Prader), and urinary gonadotropins and salivary sex hormones (testosterone and dehydroepiandrosterone sulfate) measurements. The research is expected to 1) increase the knowledge on possible risks of PYR and OP insecticides’ exposure for neurodevelopment and hormonal status in pubertal boys; 2) help to recognise deficiencies and assess available methodology for evaluation of developmental neurotoxicity and endocrine disruption within the framework of regulatory toxicology; 3) improve the insufficient methodology for exposure assessment of non-bioaccumulative pesticides; 4) contribute to the better characterisation of pesticide exposure in the Croatian population.
The project is funded by the Croatian Science Foundation. Expected project duration is 1 February 2020 – 31 October 2024.
Izloženost piretroidnim i organofosfatnim insekticidima u djece – procjena rizika od štetnih učinaka na neuropsihološki razvoj i hormonski status
Epidemiološka istraživanja i pokusi na životinjama upućuju na moguće štetne učinke piretroidnih (PYR) i organofosfatnih (OP) insekticida na razvoj mozga i spolni razvoj u djece, čak i pri vrlo niskim razinama izloženosti. Međutim, moguća povezanost izloženosti pesticidima s navedenim zdravstvenim parametrima malo je istraživana za razdoblje puberteta, uz nejednoznačne rezultate i znatna metodološka ograničenja, kao što su nedovoljno definirana izloženost i presječni dizajn studija. Glavni cilj predloženog projekta je procijeniti rizik od štetnih učinaka izloženosti PYR i OP insekticidima na neuropsihološki razvoj i hormonski status dječaka u predpubertetu i pubertetu u 2-godišnjoj kohortnoj studiji, uz kontrolu za potencijalne čimbenike utjecaja, koristeći isključivo neinvazivne metode. Izloženost djece PYR i OP insekticidima procjenjivat će mjerenjem njihovih metabolita u urinu u 5. i 7. razredu osnovne škole, te procjenom unosa pesticida hranom pomoću 24-satnog prisjećanja o prehrani u pet navrata tijekom 2-godišnjeg praćenja. U 5. i 7. razredu osnovne škole procjenjivat će se neuropsihološki razvoj testiranjem pažnje, pamćenja i brzine jednostavne psihomotorne reakcije, procjenom karakteristika spavanja i neurobihevioralnog funkcioniranja, a pubertetski razvoj procjenjivat će se pomoću kliničkog pregleda (po Tanneru i Praderu), mjerenja gonadotropina u urinu te spolnih hormona (testosterona i dehidroepiandrosteron sulfata) u slini. Očekuje se da će istraživanje doprinijeti 1) razumijevanju rizika od mogućih štetnih učinaka PYR i OP insekticida na neuropsihološki razvoj i hormonski status dječaka u pubertetu; 2) prepoznavanju nedostataka i unaprjeđenju danas raspoložive metodologije ocjenjivanja razvojne neurotoksičnosti i endokrine disrupcije u okviru regulatorne toksikologije; 3) razvoju metodologije za procjenu izloženosti pesticidima koji nemaju osobinu nakupljanja u tijelu; 4) boljoj karakterizaciji izloženosti pesticidima u hrvatskoj populaciji.
Projekt financira Hrvatska zaklada za znanost. Predviđeno trajanje projekta je od 1. veljače 2020. do 31. listopada 2024.