Association of perinatal exposition to xenobiotics with kidney volume at birth

The state of Aguascalientes has the highest prevalence of kidney failure in young adults globally. A low nephron endowment has been suggested as a possible aetiology. This study aims to evaluate the association between exposure to xenobiotics and low kidney volume (KV) at birth.

This is a cross-sectional, observational, descriptive study of at-term pregnant women with no comorbidities. We collected the mother's urine (MU) and amniotic fluid (AF) and the neonate's urine (NU). Metals and non-metals were measured with inductively coupled plasma mass spectrometry, pesticides with high-performance liquid chromatography and fluoride with ion-selective potentiometry. The total KV adjusted by body surface area (TKVBS) was calculated based on the kidney ultrasound.

Between March 2022 and July 2023, we included 299 women with an average age of 24.2 years [standard deviation (SD) 5.1]. A total of 54.2% of neonates were male with an average weight of 3266 g (SD 399). Factors associated with TKVBS ≤5th percentile were female sex, weight gain during pregnancy, glomerular filtration rate, methomyl concentration in AF {odds ratio [OR] 7.41 [95% confidence interval (CI) 2.31-23.8], P = .001}, 2,4-dichlorophenoxyacetic (2,4-D) >10 ng/ml in AF [OR 4.99 (95% CI 1.58-15.7), P = .002], MU [OR 6.1 (95% CI 1.9-19.7), P = 0.002] and NU [OR 5.1 (95% CI 1.10-26.2), P = .023] and fluoride in MU [OR 5.1 (95% CI 1.10-23.5), P = .010] and AF [OR 6.76 (95% CI 1.28-35.7), P = .024]. In all matrices (MU, AF and NU), exposure to pesticides was also significantly associated with greater concentrations of electrolytes (sodium, potassium, calcium, phosphate and magnesium) and trace elements (zinc and iron).

In neonates born to at-term women with no comorbidities, the presence of pesticides and fluoride was associated with low KV. The significant loss of electrolytes and trace elements associated with pesticides suggests proximal tubulopathy.