Global assessment of chemical quality of drinking water: The case of trihalomethanes.

BACKGROUND: Trihalomethanes (THM), a major class of disinfection by-products, are widespread and are associated with adverse health effects. We conducted a global evaluation of current THM regulations and concentrations in drinking water. METHODS: We included 120 countries (∼7000 million inhabitants in 2016), representing 94% of the world population. We searched for country regulations and THM routine monitoring data using a questionnaire addressed to referent contacts. Scientific and gray literature was reviewed where contacts were not identified or declined participation. We obtained or estimated annual average THM concentrations, weighted to the population served when possible. RESULTS: Drinking water regulations were ascertained for 116/120 (97%) countries, with 89/116 (77%) including THM regulations. Routine monitoring was implemented in 47/89 (53%) of countries with THM regulations. THM data with a varying population coverage was obtained for 69/120 (58%) countries consisting of ∼5600 million inhabitants (76% of world's population in 2016). Population coverage was ≥90% in 14 countries, mostly in the Global North, 50-89% in 19 countries, 11-49% among 21 countries, and ≤10% in 14 countries including India, China, Russian Federation and Nigeria (40% of world's population). DISCUSSION: An enormous gap exists in THM regulatory status, routine monitoring practice, reporting and data availability among countries, especially between high- vs. low- and middle-income countries (LMICs). More efforts are warranted to regulate and systematically assess chemical quality of drinking water, centralize, harmonize, and openly report data, particularly in LMICs.

Epidemiological evaluation of notifications of environmental events in the State of São Paulo, Brazil.

Increasing urbanization across the globe, combined with an increased use of chemicals in various regions, contributes to several environmental events that influence environmental health. Measures that identify environmental factors and events should be introduced to facilitate epidemiological investigations by health services. The Brazilian Ministry of Health published a new list of notifiable diseases on 25 January 2011 and introduced environmental events as a new category of notifiable occurrences. The Center for Epidemiologic Surveillance in State of Sao Paulo, Brazil, created an online notification system that highlights "environmental events", such as exposure to chemical contaminants, drinking water with contaminants outside of the recommended range, contaminated air, and natural or anthropogenic disasters. This paper analyzed 300 notifications received between May 2011 and May 2012. It reports the number of notifications with event classifications and analyzes the events relating to accidents with chemical substances. This paper describes the characteristics of the accidents that involved chemical substances, methods used, types of substances, exposed population, and measures adopted. The online notification of environmental events increases the analysis of the main events associated with diseases related to environmental chemicals; thus, it facilitates the adoption of public policies to prevent environmental health problems.