Mercury (Hg) exposure and its effects on Saudi breastfed infant's neurodevelopment

Autor: Tahreer Al-Rajudi, Chafica Eltabache, Rola Elkhatib, Iman Al-Saleh, Reem Al-Rouqi, Michael Nester, Mai Abduljabbar
Rok vydání: 2016
Předmět:
Adult
Male
Pediatrics
medicine.medical_specialty
Adolescent
Developmental Disabilities
Population
Saudi Arabia
Denver Developmental Screening Test
Breastfeeding
Mothers
Urine
010501 environmental sciences
Breast milk
01 natural sciences
Young Adult
03 medical and health sciences
chemistry.chemical_compound
Child Development
0302 clinical medicine
Humans
Medicine
030212 general & internal medicine
education
Methylmercury
0105 earth and related environmental sciences
Psychomotor learning
education.field_of_study
Reference dose
Milk
Human

business.industry
Public Health
Environmental and Occupational Health

Infant
Mercury
Methylmercury Compounds
Middle Aged
Breast Feeding
Cross-Sectional Studies
chemistry
Maternal Exposure
Female
business
Water Pollutants
Chemical

Environmental Monitoring
Hair
Zdroj: International Journal of Hygiene and Environmental Health. 219:129-141
ISSN: 1438-4639
DOI: 10.1016/j.ijheh.2015.10.002
Popis: This cross-sectional study analyzed mercury (Hg) levels in healthy Saudi mothers and their infants (age 3-12 months) and examined the influence of Hg on the infants' neurodevelopment using screening tools, such as the Denver Developmental Screening Test II (DDST-II) and Parents' Evaluation of Developmental Status (PEDS). A total of 944 mothers and their 944 infants were recruited from 57 Primary Health Care Centers (PHCCs) in Riyadh. The total Hg (THg) levels were measured in the mothers' and infants' urine (UTHg-M and UTHg-I) and hair (HTHg-M and HTHg-I) samples and in the breast milk and mothers' blood. Methylmercury (MeHg) levels were determined in hair samples from the mothers (MeHg-M) and infants (MeHg-I). Only 40.1% of the infants were breast-fed when enrolled, and 59.9% had stopped breastfeeding. Only 1.8% of the mothers and 0.3% of the infants had MeHg levels above the Environmental Proection Agency (EPA) reference dose (1 μg/g), with low medians of 0.132 and 0.091 μg/g dw, respectively, but the MeHg levels were significantly associated with infant DDST-II performance. The levels of corrected UTHg-M for creatinine (Cr), HTHg-M, HTHg-I, and HMeHg-M, however, displayed an association with infant PEDS performance. The medians and percentage of the tested population that exceeded the recommended limits for Hg in urine and hair set by the World Health Organization (5 μg/g Cr) and EPA (1 μg/g) were 0.695 μg/g Cr and 3% UTHg, 0.118 μg/g dw and 4.1% HTHg-M, 0.101 μg/g dw and 2.8% HTHg-I, and 0.132 μg/g dw and 1.8% HMeHg-M. Our study provides evidence of an association between some Hg measures and delays in infant neurodevelopment, despite their low levels and regardless of the infant's breastfeeding status. The results are of potential concern, because delayed psychomotor or mental performance in infants could be an indicator of later neurocognitive development in children, which may persist into adulthood, as shown in other studies. The absence of local standardization of the DDST-II and PEDS screening tools might raise some questions, although the DDST-II has been used in local institutions for a number of years. The development of effective standardized developmental screening tools is necessary to ensure that all children at risk of neurodevelopmental problems early in life are identified so that they can receive appropriate and timely intervention.
Databáze: OpenAIRE