Prenatal Exposure to Mercury, Fish Consumption During Pregnancy and Associated Factors in Four Spanish Birth Cohorts (INMA Project)

Abstract

ISEE-0561 Background and Objective: High prenatal exposure to mercury (Hg) has been related with neurodevelopmental deficits in children. Fish consumption is the main source of Hg exposure. Our objective is to assess total Hg (T-Hg) exposure in newborn and associated factors in 4 cohorts of the Spanish Environment and Childhood (INMA) Project. Methods: Study population included 1,888 mother and child pairs from 4 areas of Spain, i.e. Asturias (340), Gipuzkoa (533), Sabadell (461), and Valencia (554). T-Hg concentration in cord blood was determined by atomic absorption spectrometry. Information on socio-demographic characteristics, occupational history, and life-style was obtained through 3 questionnaires completed in the 1st and 3rd trimester of pregnancy. Fish intake was assessed by a food frequency questionnaire at 3rd trimester that included eleven items for fish intake. ANCOVA was used for multivariate analysis. Results: T-Hg levels were below LOD in 89 samples (4.7%). Geometric mean (interquartile range) for each cohort was 10.8 μg/L (6.6–18.8), 7.5 (5.1–12.0), 6.3 (4.1–10.0), and 9.5 (5.3–18.0), respectively. Sixty-eight percent of samples showed T-Hg levels above the EPA reference dose equivalent (5.8 μg/L). The mean daily fish intake was 73 g/day; white fish, canned tuna, and big oily fish provided the main contribution to fish intake. Statistically significant increases of 12.5, 7.6, 6.7 and 3.4% in T-Hg levels were observed for 100 g/week increase in the intake of big oily fish, white fish, canned tuna and the remaining fish, respectively. Conclusion: We found elevated T-Hg levels in cord blood in Spain similar to other high consumption populations. It is necessary to develop actions to prevent high prenatal exposure to mercury including guidance to pregnant women in making prudent dietary choices as well as public health control of Hg concentration in marketed fish. Funding: ISCIII (INMAG03/176, FIS: 03/1615, 04/1112, 04/1509, 06/1213) and Conselleria Sanitat-GV, Spain.