title: Contamination from endocrine disrupters of the general population at low and high concentrations.
abstract: Analyses of the concentrations of a given environmental compound usually show that most citizens have much lower concentrations than a certain minority, whose members have high body concentrations. Surveys of human exposure to chemicals do not usually integrate the number of chemical compounds detected per person and the concentration of each compound. This leaves untested relevant exposure situations, for example, whether individuals with low concentrations of some compounds have high concentrations of the other compounds. On scientific grounds, it is puzzling that this possibility, arithmetically and conceptually rather simple, has seldom if ever been tested in studies based on a representative sample of the general population. A study based on a representative sample of the general population of Catalonia (Spain) (Porta, Pumarega, & Gasull, 2012), which integrated the number of compounds detected per person and the concentration of each compound, found that more than half of the population had concentrations in the top quartile of 1 or more of the 19 persistent toxic substances (PTS) (pesticides and polychlorinated biphenyls) analyzed. Significant subgroups of the population accumulated PTS mixtures at high concentrations. For instance, 48% of women 60-74 years had concentrations of 6 or more PTS in the top quartile; half of the entire population had levels of 1-5 PTS above 500 ng/g, and less than 4% of citizens had all PTS in the lowest quartile. Thus, PTS concentrations appear low in most of the population only when each individual compound is looked at separately. It is not accurate to state that most of the population has low concentrations of PTS. The assessment of mixture effects must address the fact that most individuals are contaminated by PTS mixtures made of compounds at both low and high concentrations.
authors.affiliation: Unit of Clinical and Molecular Epidemiology of Cancer, Hospital del Mar Institute of Medical Research-IMIM, Barcelona, Catalonia, Spain; School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain; CIBER en Epidemiología y Salud Pública (CIBERESP), Spain; Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, USA. Electronic address: mporta@imim.es.
authors.forename: Miquel
authors.initials: M
authors.lastname: Porta
authors.affiliation: Unit of Clinical and Molecular Epidemiology of Cancer, Hospital del Mar Institute of Medical Research-IMIM, Barcelona, Catalonia, Spain; CIBER en Epidemiología y Salud Pública (CIBERESP), Spain.
authors.forename: José
authors.initials: J
authors.lastname: Pumarega
authors.affiliation: Unit of Clinical and Molecular Epidemiology of Cancer, Hospital del Mar Institute of Medical Research-IMIM, Barcelona, Catalonia, Spain; CIBER en Epidemiología y Salud Pública (CIBERESP), Spain.
authors.forename: Magda
authors.initials: M
authors.lastname: Gasull
authors.affiliation: Unit of Clinical and Molecular Epidemiology of Cancer, Hospital del Mar Institute of Medical Research-IMIM, Barcelona, Catalonia, Spain; School of Medicine, Universitat Autònoma de Barcelona, Barcelona, Spain; CIBER en Epidemiología y Salud Pública (CIBERESP), Spain.
authors.forename: Tomàs
authors.initials: T
authors.lastname: Lopez
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D000818:Animals; D035843:Biomedical Research; D001822:Body Burden; D002648:Child; D054750:Ecotoxicology / Q000379:methods; D052244:Endocrine Disruptors / Q000032:analysis / Q000633:toxicity*; D004781:Environmental Exposure / Q000009:adverse effects*; D004785:Environmental Pollutants / Q000032:analysis / Q000633:toxicity*; D005260:Female; D014943:Global Health; D006801:Humans; D008297:Male; D012107:Research Design; D012727:Sex Characteristics
chemical_list: D052244:Endocrine Disruptors; D004785:Environmental Pollutants
keywords: Environmental exposure/adverse effects; Environmental pollutants/prevention and control; Health survey; Human biomonitoring; Low doses; Persistent organic pollutants