Swimming pool water disinfection by-products profiles and association patterns

The aim of this work was to determine and study the concentration of different groups of disinfection by-products (DBPs): trihalomethanes, haloacetic acids, haloacetonitriles, haloacetones and combined chlorine (as an indicator of chloramine levels), in the water of 175 public swimming pools in Gipuzkoa (Basque Country, Spain). The study included chlorinated and brominated pools, indoor and outdoor, used for recreational and sports purposes, and filled with water from calcareous and siliceous soils. The most abundant were haloacetic acids, followed by trihalomethanes, with chlorinated or brominated forms predominating depending on whether the pools were disinfected by chlorination or bromination, respectively. All the 75th percentiles of DBPs were below the limits established by the European Chemical Agency (ECHA), although the maximum values of trihalomethanes exceeded them. The same was true for dichloroacetonitrile in chlorinated pools and dibromoacetonitrile in brominated pools. All families of DBPs showed positive associations with each other, all being significant except for combined chlorine. Their mean levels were higher in outdoor pools than in indoor pools, significantly so in all except combined chlorine. Recreational pools showed higher levels of haloacetic acids and combined chlorine than sports pools. The concentrations of the different groups of DBPs were higher in the pools than in the mains water that fed them. This increase, especially that of the haloacetonitriles, as well as the high concentrations of brominated forms in the pools disinfected by bromination, make it necessary to focus on their toxicological implication. The differences in the DBP profiles of the filling network water were not transferred to the pool water.

Serum metal levels in a population of Spanish pregnant women

OBJECTIVE

To describe serum levels of calcium, copper, selenium, magnesium, iron and zinc and evaluate their relationship with maternal socio-demographic characteristics and dietary variables in women in the first trimester of pregnancy.

METHOD

Cross-sectional study with 1279 participants from the INMA cohorts.

RESULTS

The concentrations of the elements analyzed were within the normal range. Associations with higher levels of these metals were found for calcium with white meat intake (p=0.026), for copper with excess body weight (p <0.01), low social class (p=0.03) and being multipara (p <0.01), for magnesium with being over 35 years old (p=0.001), high social class (p=0.044), primiparous status (p=0.002) and low daily intake of bread (p=0.009) and legumes (p=0.020); for zinc with university education (p=0.039) and residence in Gipuzkoa (p <0.01), and for selenium with residence in Valencia (p <0.01), university education (p=0.001), vitamin B₆ supplementation (p=0.006), fish intake (> 71g/day) (p=0.014) and having been born in Spain (p=0.001). Further, lower iron levels were associated with being overweight (p=0.021) or obese (p <0.001) and vitamin B₁₂ supplementation (p=0.006).

CONCLUSIONS

Our results suggest that trace elements in the analyzed cohorts are adequate for this stage of pregnancy. The variability in these elements is mainly linked to socio-demographic and anthropometric variables.

Prenatal exposure to PM2.5 and NO2 and sex-dependent infant cognitive and motor development

BACKGROUND

Prenatal exposure to air pollutants including particulate matter (<2.5 μm of diameter,PM_2.5)and nitrogen dioxide (NO₂) has been identified as a potential risk factor for neuropsychological developmental and mental health disorders.

OBJECTIVE

This study aimed to analyze the associations between prenatal PM_2.5 and NO₂ exposure and cognitive functions in children at 4-6 years of age, including sex differences, and the modification effect of the duration predominant breastfeeding these associations.

DESIGN

This study was conducted as part of the INMA project, a population-based birth cohort study in Spain (n = 1119). Each of the pregnant mothers was assigned a prenatal exposure to PM_2.5 and NO₂ for their whole pregnancy based on their place of residence. At the 4-6 year-old follow-up, infants' neuropsychological development was assessed using McCarthy scales: Verbal, Perceptive-Manipulative, Numeric, General Cognitive, Memory and Motor (gross and fine). Between 6 and 14 months of age, information concerning breastfeeding was gathered with a questionnaire. Regression analyses were performed to estimate the associations between exposure and outcomes, accounting for potential confounders. The analyses were stratified by child sex and breastfeeding duration.

RESULTS

The majority of coefficients for the different cognitive domains were negative either for PM_2.5 and NO₂, though none was statistically significant. After stratifying by sex, the associations become even more negative for boys, with some of the associations becoming statistically significant (memory both for PM_2.5 and NO₂), and global cognition and verbal for NO₂. Duration of predominant breastfeeding was not found to have a modifying effect.

CONCLUSIONS

These findings suggest a sex-dependent effects on neuropsychological development at 4-6 years of age, with a greater vulnerability in boys, specifically in domains related to memory, verbal and general cognition. No modifying effect was observed for duration of predominant breastfeeding.

Exposure to extremely low and intermediate-frequency magnetic and electric fields among children from the INMA-Gipuzkoa cohort

Detailed assessment of exposure to extremely low frequency (ELF) and intermediate frequency (IF) fields is essential in order to conduct informative epidemiological studies of the health effects from exposure to these fields. There is limited information available regarding ELF electric fields and on both magnetic and electric field exposures of children in the IF range. The aim of this study was to characterize ELF and IF exposure of children in the Spanish INMA cohort. A combination of spot and fixed measurements was carried out in 104 homes, 26 schools and their playgrounds and 105 parks. Low levels of ELF magnetic fields (ELF-MF) were observed (with the highest 24-h time-weighted average (TWA) exposure being 0.15μT in one home). The interquartile range (IQR) of ELF electric fields (ELF-EF) ranged from 1 to 15V/m indoors and from 0.3 to 1.1V/m outdoors and a maximum value observed was 55.5V/m in one school playground. IQR ranges for IF magnetic and electric fields were between 0.02 and 0.23μT and 0.2 and 0.5V/m respectively and maximum values were 0.03μT and 1.51V/m in homes. Correlations between magnetic and electric fields were weak for ELF (Spearman 0.04-0.36 in different settings) and moderate for IF (between 0.28 and 0.75). Children of INMA-Gipuzkoa cohort were exposed to very low levels of ELF-MF in all settings and to similar levels of ELF-EF compared to the range of previously reported levels, although somewhat higher exposures occurred at home. Children enrolled to our study were similarly exposed to IF in all settings.

[Fluoride intake through consumption of water from municipal network in the INMA-Gipuzkoa cohort]

OBJECTIVE

To estimate fluoride intake through consumption of water from the municipal network in pregnant women and their children from the INMA-Gipuzkoa cohort and to compare these intakes with recommended levels. In Euskadi (Spain), fluoridation of drinking water is compulsory in water supplies for more than 30,000 inhabitants.

METHOD

575 pregnant women (recruitment, 2006-2008) and 424 4-year-old children (follow-up, 2010-2012) have been included. Fluoride levels in drinking water were obtained from the water consumption information system of the Basque Country (EKUIS). Water consumption habits and socioeconomic variables were obtained by questionnaire.

RESULTS

74.9% and 87.7% of women and children consumed water from the municipal network. Average fluoride levels in fluoridated water were 0.805 (SD: 0.194) mg/L during baseline recruitment and 0.843 (SD: 0.080) mg/L during follow up, at 4 years old of the children. Average and 95th percentile of fluoride intake were 0.015 and 0.026mg/kg per day in women and 0.033 and 0.059mg/kg per day in children. Considering only fluoride provided by drinking water, 8.71% of children living in fluoridated areas exceeded intake level recommended by the European Food Safety Authority, consisting in 0.05mg/kg per day.

CONCLUSION

The results show that ingested levels of fluoride through consumption of municipal water can exceed the recommended levels in children and encourages further studies that will help in fluoridation policies of drinking water in the future.

Exposure to fine particle matter, nitrogen dioxide and benzene during pregnancy and cognitive and psychomotor developments in children at 15 months of age

BACKGROUND

Prenatal exposure to air pollutants has recently been identified as a potential risk factor for neuropsychological impairment.

OBJECTIVES

To assess whether prenatal exposure to fine particulate matter (PM2.5), nitrogen dioxide (NO2) and benzene were associated with impaired development in infants during their second year of life.

METHODS

Regression analyses, based on 438 mother-child pairs, were performed to estimate the association between mother exposure to air pollutants during pregnancy and neurodevelopment of the child. The average exposure to PM2.5, NO2 and benzene over the whole pregnancy was calculated for each woman. During the second year of life, infant neuropsychological development was assessed using the Bayley Scales of Infant Development. Regression analyses were performed to estimate the association between exposure and outcomes, accounting for potential confounders.

RESULTS

We estimated that a 1 μg/m(3) increase during pregnancy in the average levels of PM2.5 was associated with a -1.14 point decrease in motor score (90% CI: -1.75; -0.53) and that a 1 μg/m(3) increase of NO2 exposure was associated with a -0.29 point decrease in mental score (90% CI: -0.47; -0.11). Benzene did not show any significant association with development. Considering women living closer (≤ 100 m) to metal processing activities, we found that motor scores decreased by -3.20 (90% CI: -5.18; -1.21) for PM2.5 and -0.51 (-0.89; -0.13) for NO2, while mental score decreased by -2.71 (90% CI: -4.69; -0.74) for PM2.5, and -0.41 (9% CI: -0.76; -0.06) for NO2.

CONCLUSIONS

Our findings suggest that prenatal residential exposure to PM2.5 and NO2 adversely affects infant motor and cognitive developments. This negative effect could be higher in the proximity of metal processing plants.

Air Polycyclic Aromatic Hydrocarbons (PAHs) associated with PM2.5 in a North Cantabric coast urban environment

Health studies and more specifically epidemiological studies require an extended analysis of the physical and chemical characteristics of the environment in which are held. The aim of this study is to evaluate the concentration of six Polycyclic Aromatic Hydrocarbons (PAHs) in PM2.5 fraction of air in a peri-urban environment in the province of Gipuzkoa (Basque Country, Spain) where residential areas are surrounded by industrial activity. The six studied PAH are as follows: Fluoranthene, Benzo(b)fluoranthene, Benzo(k)fluoranthene, (Benzo(a)pyrene, Indene(123-cd)pyrene and Benzo(ghi)perylene. Our six-year study shows a decrease in PAH concentrations between 2006 and 2011, especially since 2008 due to the fall in industrial activity and related traffic. Overall, 801 data were obtained. Total PAH concentration ranged between 0.3 and 8.29ngm(-3) and Benzo(a)pyrene (BaP) from 0.05 to 0.88ngm(-3). The mean value for BaP in PM2.5 was 0.15ngm(-3) and the target value established by European legislation in PM10 was only exceeded in occasional days. Contribution percentages of each PAH in the monitoring sites were very similar, indicating common sources. The results of this study suggest that emission from industry play an important role although we also have to consider the contribution of traffic. PAH seasonal variations are similar as those reported in many previous studies. BaP and PAH concentration values in our region of study were in the range of other Spanish cities.