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. 2022 Oct 14:10:952559.
doi: 10.3389/fped.2022.952559. eCollection 2022.

Chlorpyrifos residue level and ADHD among children aged 1-6 years in rural China: A cross-sectional study

Wenjuan Zhou  1 , Yuanying Deng  1 , Chen Zhang  1 , Hongmei Dai  1 , Lan Guan  2 , Xiangwen Luo  3 , Wei He  1 , Jing Tian  1 , Lingling Zhao  1
Affiliations

Chlorpyrifos residue level and ADHD among children aged 1-6 years in rural China: A cross-sectional study

Wenjuan Zhou et al. Front Pediatr. .

Abstract

Background: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood and is caused by both genetic and environmental factors. As genetic factors are nonmodifiable, environmental factors have attracted increasing attention.

Objective: To investigate the relationships between urinary chlorpyrifos (CPF) levels, blood micronutrient levels, and ADHD prevalence in children living in rural areas of China.

Methods: This cross-sectional study collected data on CPF exposure (according to urinary levels), blood micronutrient levels, and ADHD prevalence in children aged 1-6 years in rural China. The CPF levels were determined by mass spectrometry. Blood levels of micronutrients, including zinc, iron, calcium, copper, magnesium, and vitamin D, were measured by professional detection kits. ADHD was diagnosed according to the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition. Descriptive statistics and univariate analysis were conducted using SPSS 21.0, and path analysis was conducted using Mplus 8.0.

Results: Of the 738 children who met the eligibility criteria, 673 children (673/738, 91.2%) were included in the final analysis. Baseline questionnaires and urine samples were collected from all 673 subjects. A total of 672 children provided blood samples for micronutrient testing, and 651 completed the ADHD assessment. Approximately one-fifth of children (144/673, 21.4%) had detectable levels of CPF in their urine, and 6.9% (45/651) were diagnosed with ADHD. Path analysis showed that the total effect of CPF exposure on ADHD risk was 0.166 (P < 0.05), with a direct effect of 0.197 (P < 0.05) and an indirect effect of -0.031 (P < 0.05) via vitamin D. The mediating effect of urinary CPF levels on ADHD risk via vitamin D was 18.67%.

Conclusion: Higher levels of CPF exposure are associated with higher risk of ADHD. Additionally, increasing vitamin D levels may have a beneficial effect on the relationship between CPF exposure and ADHD risk. Our findings highlight the importance of modifying environmental factors to reduce ADHD risk and provide insight into future ADHD interventions.

Keywords: ADHD; children; chlorpyrifos; cross-sectional study; micronutrients; vitamin D.

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Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

Figure 1
Figure 1
Research population and survey flow chart.
Figure 2
Figure 2
Histogram of chlorpyrifos concentrations detected in urine samples and the corresponding number of positive samples.
Figure 3
Figure 3
Model linking chlorpyrifos exposure to ADHD. Note: * indicates P < 0.05, statistically significant effects are indicated by solid lines.
See this image and copyright information in PMC

References

    1. Arruda MA, Querido CN, Bigal ME, Polanczyk GV. ADHD And mental health status in Brazilian school-age children. J Atten Disord. (2015) 19(1):11–7. 10.1177/1087054712446811 - DOI - PubMed
    1. Thapar A, Cooper M, Eyre O, Langley K. What have we learnt about the causes of ADHD? J Child Psychol Psychiatry. (2013) 54(1):3–16. 10.1111/j.1469-7610.2012.02611.x - DOI - PMC - PubMed
    1. Del-Ponte B, Quinte GC, Cruz S, Grellert M, Santos IS. Dietary patterns and attention deficit/hyperactivity disorder (ADHD): a systematic review and meta-analysis. J Affect Disord. (2019) 252:160–73. 10.1016/j.jad.2019.04.061 - DOI - PubMed
    1. Li Y, Zhang H, Kuang H, Fan R, Cha C, Li G, et al. Relationship between bisphenol A exposure and attention-deficit/ hyperactivity disorder: a case-control study for primary school children in Guangzhou, China. Environ Pollut. (2018) 235:141–9. 10.1016/j.envpol.2017.12.056 - DOI - PubMed
    1. Perera FP, Chang HW, Tang D, Roen EL, Herbstman J, Margolis A, et al. Early-life exposure to polycyclic aromatic hydrocarbons and ADHD behavior problems. Plos One. (2014) 9(11):e111670. 10.1371/journal.pone.0111670 - DOI - PMC - PubMed

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