Sex specific associations between in utero exposure to persistent organic pollutants and allergy-related outcomes in childhood: The Rhea Mother-Child Cohort (Crete, Greece)

Systematic investigation of organochlorine pesticides and polychlorinated biphenyls blood levels in Greek children from the Rhea birth cohort suggests historical exposure to DDT and through diet to DDE

The blood levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) have been thoroughly investigated in Greek children from the Rhea birth cohort study. This investigation aimed to assess exposure levels, explore their possible relationship with children's age and sex, and indicate potential sources of exposure. Exposure patterns and common sources of PCBs and OCPs were analyzed using bivariate and multivariate statistics. A total of 947 blood samples from study participants were analyzed for OCP and PCB exposure, with 375 samples collected at 4 years old, 239 at 6.5 years old, and 333 at 11 years old. Elevated levels of DDE were observed in 6.5-year-old children compared to corresponding levels in other European countries. Higher levels of DDE were found in 4-year-old children, with the lowest concentrations in the 11-year-old group. The DDT/DDE ratio was consistently less than 1 among all the examined subjects. These results indicate exposure to DDT and DDE both in utero and through breastfeeding and dietary intake. For the entire cohort population, the highest concentration was determined for PCB 28, followed by PCBs 138, 153, and 180. The sum of the six indicator PCBs implied low exposure levels for the majority of the cohort population. Spearman correlations revealed strong associations between PCBs and OCPs, while principal component analysis identified two different groupings of exposure. DDE exhibited a correlation with a series of PCBs (153, 156, 163, 180), indicating a combined OCP-PCB source, and an anticorrelation with others (52, 28, 101), implying a separate and competing source.

Features of Spleen Development in Newborn Rats Exposed to Endocrine Disrupter Dichlorodiphenyltrichloroethane during the Prenatal Period

The development of the spleen in newborn male Wistar rats exposed to low-dose endocrine disruptor dichlorodiphenyltrichloroethane during the prenatal period was studied. Histological examination of the spleen revealed a more active development of periarterial lymphoid sheaths and lower granulocyte content in the organ. Cytofluorimetry showed a significantly lower content of B cells. Thus, low-dose exposure of the endocrine disruptor dichlorodiphenyltrichloroethane on the developing organism during the prenatal period induced changes in spleen morphogenesis resulting in extensive development of lymphoid formations and a lower intensity of lymphocyte and granulocyte differentiation.

Associations of gestational and early-life exposure to toxic metals and fluoride with a diagnosis of food allergy or atopic eczema at 1 year of age

Studies have indicated that early-life exposure to toxic metals and fluoride affects the immune system, but evidence regarding their role in allergic disease development is scarce. We aimed to evaluate the relations of exposure to such compounds in 482 pregnant women and their infants (4 months of age) with food allergy and atopic eczema diagnosed by a paediatric allergologist at 1 year of age within the Swedish birth-cohort NICE (Nutritional impact on Immunological maturation during Childhood in relation to the Environment). Urinary cadmium and erythrocyte cadmium, lead, and mercury concentrations were measured by inductively coupled plasma mass spectrometry (ICP-MS), urinary inorganic arsenic metabolites by ICP-MS after separation by ion exchange chromatography, and urinary fluoride by an ion-selective electrode. The prevalence of food allergy and atopic eczema was 8 and 7%, respectively. Gestational urinary cadmium, reflecting chronic exposure, was associated with increased odds of infant food allergy (OR [95% CI]: 1.34 [1.09, 1.66] per IQR [0.08 μg/L]). Both gestational and infant urinary fluoride were associated, albeit at a statistically non-significant level, with increased atopic eczema odds (1.48 [0.98, 2.25], 1.36 [0.95, 1.95], per doubling, respectively). By contrast, gestational and infant erythrocyte lead was associated with decreased odds of atopic eczema (0.48 [0.26, 0.87] per IQR [6.6 μg/kg] and 0.38 [0.16, 0.91] per IQR [5.94 μg/kg], respectively), and infant lead with decreased odds of food allergy (0.39 [0.16, 0.93] per IQR [5.94 μg/kg]). Multivariable adjustment had marginal impact on the estimates above. After additional adjustment for fish intake biomarkers, the methylmercury associated atopic-eczema odds were considerably increased (1.29 [0.80, 2.06] per IQR [1.36 μg/kg]). In conclusion, our results indicate that gestational cadmium exposure might be associated with food allergy at 1 year of age and, possibly, early-life exposure to fluoride with atopic eczema. Further prospective and mechanistic studies are needed to establish causality.

Maternal pesticides exposure in pregnancy and the risk of wheezing in infancy: A prospective cohort study

INTRODUCTION

Pesticide exposure in pregnancy may have health effects in the offspring. We studied whether maternal pesticides exposure during pregnancy is associated with infant wheezing.

METHODS

The study involved 5997 children from the Italian NINFEA birth cohort, whose mothers were recruited during pregnancy between 2005 and 2016. We used questionnaires completed during pregnancy and 6 months after delivery to derive the following indirect measures of exposure: i) Self-reported pesticide use during the first and the third trimester of pregnancy; (ii) Agricultural activities during the same trimesters. We also evaluated the exposure to agricultural pesticides applied near home using the Corine Land Cover inventory to derive the proportion of a 200-metre buffer area around maternal home address covered by agricultural crops and specific crop types (arable land, fruit trees, heterogeneous cultivations). Questionnaires completed when the child turned 18 months reported information on wheezing between 6 and 18 months of age. We estimated the odds ratios of wheezing adjusting for the following maternal characteristics: age, education, parity, asthma, atopy, smoking in pregnancy, region and area of residence, pet ownership during pregnancy. Crops proximity analyses were restricted to residents in rural areas (N = 1674).

RESULTS

Agricultural activities during pregnancy were not associated with infant wheezing. Compared to no pesticide use, there was a weak positive association for self-reported use in the third trimester (POR: 1.30; 95 %CI 0.95-1.78) and a stronger association for use in both trimesters (POR: 1.72; 95 %CI 1.11-2.65). The relationship between the proportion of crops around the home address and the risk of infant wheezing, was J-shaped, in particular for fruit trees with the lowest risk for mid values and elevated risk for higher values.

CONCLUSION

We found some evidence of association for maternal pesticide use in pregnancy and residential proximity to fruit trees cultivations with infant wheezing.