Drinking water nitrate and prevalence of methemoglobinemia among infants and children aged 1-7 years in Moroccan areas.

CONTEXT: Nitrate is ubiquitous in environmental media (air, water and soil) and other sources (some medicines, inorganic fertilizers and household's chemicals). It is a hemoglobin-oxidizing agent that can cause methemoglobinemia. The effect of nitrate on infants is well known but less is known about nitrate-induced methemoglobinemia in young children. METHOD: Two cross-sectional studies were carried out in Salé, Morocco to determine the prevalence of methemoglobinemia among 411 infants and children aged 1-7 years in two adjacent areas that were similar in terms of the air quality, available vegetables and medicines but different in terms of the drinking water quality (nitrate-contaminated well water versus municipal water). RESULTS: In the exposed area, nitrate concentration was measured in 78 wells and ranged from 15.39 to 246.90mg/l as NO3-. Nitrate levels were higher than 50mg/l in 69.2% of the surveyed wells, and 64.2% of the participants were drinking nitrate contaminated well waters. The prevalence of methemoglobinemia among study children was 36.2% in the exposed area, and 27.4% in the non-exposed area. Study children drinking well water with a nitrate concentration >50mg/l were significantly more likely to have methemoglobinemia than those drinking well water with a nitrate concentration <50mg/l (p=0.001 at 95% CI=[1.22-2.64]) or than those drinking municipal water (p<0.01 at 95% CI=[1.16-2.21]). In the exposed area, the mean methemoglobin (MetHb) level increased with age (R2= 0.79, p=0.04), whereas in the unexposed area, the mean MetHb level remained relatively stable in the first 6 years of life (R2=0.21, p=0.44). Mean MetHb was normal when the nitrate concentration in water was below 50mg/l as NO3-, and reached an abnormal level, when the nitrate concentration in water ranged between 50 and 90mg/l as NO3-. This last level was statistically similar to mean MetHb at nitrate level above 90mg/l as NO3- (up to 246.9mg/l as NO3-). No association was observed between methemoglobinemia prevalence and gender. This is the first study about methemoglobinemia conducted in Morocco.

Hair mercury levels in relation to fish consumption in a community of the Moroccan Mediterranean coast.

Coastal populations with high seafood consumption in the Mediterranean have a significant exposure to dietary methylmercury, and areas where environmental mercury pollution is an issue due to industrial activities are of special concern. The study was undertaken with the aim of assessing methylmercury exposure through fish consumption in a community of north Morocco and characterizing the relevant health risk. Concentrations of total mercury were determined in human hair, a biomarker of methylmercury exposure, and in locally consumed fish by cold vapour atomic absorption spectrophotometry. Based on consumption frequencies reported by the 108 subjects included in the study the weekly intake of methylmercury was estimated and biomarker data were evaluated in relation to the estimated intake and the sociodemographic characteristics of the population. Multiple regression analysis was employed for the interpretation of hair mercury data in relation to fish consumption frequency, gender and the age of individuals. Mercury concentrations in hair ranged from 0.22 to 9.56 microg g(-1) (geometric mean = 1.79 microg g(-1)) and were closely related to fish intake. Fisherman and their families consumed fish three to five times per week and were the most exposed population subgroup. A high proportion of women of child-bearing age (50%) had relatively high levels of mercury in their hair (3.08-7.88 microg g(-1)).

[Hospital solid waste: quantification. Bacteriological analyses--case of hospital Ibn Sina]. / Les dechets solides hospitaliers: quantification, analyses bacteriologiques du percolet--cas de l'hôpital Ibn Sina.

Hospital waste represent, by their nature and their constitution, a big threat to health in the intra and extra hospital area. and a source of pollution for the environment. A 12-day campaign of weighing of the waste produced by the hospital Ibn Sina of Rabat-Morocco should an average of 1.75 kg/bed/day. In order to identify the hospital pathogenic germs as well as their sensitivities to antibiotics, some bacteriological analyses have been done on the percolat waste of this hospital. The results of these analyses put in evidence the presence of Pseudomonas aeruginosa and Staphylococcus aureus and their resistance to some antibiotics.