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Urinary biomarkers as exposure surrogates: controlling for possible bias.

Barrett JR - Environ. Health Perspect. (2015)

View Article: PubMed Central - PubMed

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Biomonitoring, or measuring levels of contaminants and their metabolites in human biological samples, can tell researchers a good deal about the environmental agents to which populations are exposed... Participants undergo physical examination, provide biological samples such as blood and urine for laboratory testing, and complete interviews regarding health, lifestyle, socioeconomic status, and other variables... The authors of the current study used data from the 2009–2010 and 2011–2012 NHANES cycles to assess patterns in the relationship between urinary flow rate (UFR) and body weight–adjusted urinary flow rate (UFRBW)... These NHANES cycles differed from previous ones in that they collected data on the time between last and current urination and on urine volume, details that provide a more in-depth understanding of what urinary concentrations of environmental contaminants and their metabolites actually mean. “The issue of adjusting for hydration status in general—how much urine someone is producing over a period of time—is something that people in the biomonitoring community always struggle with in terms of correcting for it,” says coauthor Lesa Aylward, principal at Summit Toxicology LLP... In addition, they tested their hypotheses by focusing on urinary concentrations and analyte excretion rates (measured in nanograms per hour, with and without adjustment for body weight) among different age groups for the chemicals bisphenol A and 2,5-dichlorophenol... They compared the results with those obtained by using conventional estimation methods, such as adjusting measurements based on urine levels of the metabolite creatinine, a surrogate for hydration status... The NHANES data analyzed in the current study included information on 14,631 participants aged 6 years and older... The authors found that both UFR and UFRBW varied by age and race/ethnicity, whereas only UFR varied by sex, and only UFRBW varied by BMI... The complexity revealed by the findings of the new study is a good thing, says Krista Christensen, an epidemiologist at the Wisconsin Division of Public Health. “This complexity will help researchers to better understand, analyze, and interpret their data—and this article is a great step forward in describing the considerations needed when using urinary biomarker data,” Christensen says... She was not involved in this study but used UFR calculations in another recent study... Aylward also indicates that the study raises some broader issues. “Biomonitoring data for chemicals has really exploded in the last fifteen years,” she says. “We’re now moving into a situation where we have a more sophisticated understanding of the physiological factors that might influence the concentrations of chemicals that can be measured... We’re trying to move from being naive consumers of biomonitoring data to being more sophisticated consumers of those data. ”

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The findings from a new study may enable researchers to more accurately assess the significance of chemical concentrations in biological samples.© Tek Image/Science Source
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d35e109: The findings from a new study may enable researchers to more accurately assess the significance of chemical concentrations in biological samples.© Tek Image/Science Source


Urinary biomarkers as exposure surrogates: controlling for possible bias.

Barrett JR - Environ. Health Perspect. (2015)

The findings from a new study may enable researchers to more accurately assess the significance of chemical concentrations in biological samples.© Tek Image/Science Source
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4384196&req=5

d35e109: The findings from a new study may enable researchers to more accurately assess the significance of chemical concentrations in biological samples.© Tek Image/Science Source

View Article: PubMed Central - PubMed

AUTOMATICALLY GENERATED EXCERPT
Please rate it.

Biomonitoring, or measuring levels of contaminants and their metabolites in human biological samples, can tell researchers a good deal about the environmental agents to which populations are exposed... Participants undergo physical examination, provide biological samples such as blood and urine for laboratory testing, and complete interviews regarding health, lifestyle, socioeconomic status, and other variables... The authors of the current study used data from the 2009–2010 and 2011–2012 NHANES cycles to assess patterns in the relationship between urinary flow rate (UFR) and body weight–adjusted urinary flow rate (UFRBW)... These NHANES cycles differed from previous ones in that they collected data on the time between last and current urination and on urine volume, details that provide a more in-depth understanding of what urinary concentrations of environmental contaminants and their metabolites actually mean. “The issue of adjusting for hydration status in general—how much urine someone is producing over a period of time—is something that people in the biomonitoring community always struggle with in terms of correcting for it,” says coauthor Lesa Aylward, principal at Summit Toxicology LLP... In addition, they tested their hypotheses by focusing on urinary concentrations and analyte excretion rates (measured in nanograms per hour, with and without adjustment for body weight) among different age groups for the chemicals bisphenol A and 2,5-dichlorophenol... They compared the results with those obtained by using conventional estimation methods, such as adjusting measurements based on urine levels of the metabolite creatinine, a surrogate for hydration status... The NHANES data analyzed in the current study included information on 14,631 participants aged 6 years and older... The authors found that both UFR and UFRBW varied by age and race/ethnicity, whereas only UFR varied by sex, and only UFRBW varied by BMI... The complexity revealed by the findings of the new study is a good thing, says Krista Christensen, an epidemiologist at the Wisconsin Division of Public Health. “This complexity will help researchers to better understand, analyze, and interpret their data—and this article is a great step forward in describing the considerations needed when using urinary biomarker data,” Christensen says... She was not involved in this study but used UFR calculations in another recent study... Aylward also indicates that the study raises some broader issues. “Biomonitoring data for chemicals has really exploded in the last fifteen years,” she says. “We’re now moving into a situation where we have a more sophisticated understanding of the physiological factors that might influence the concentrations of chemicals that can be measured... We’re trying to move from being naive consumers of biomonitoring data to being more sophisticated consumers of those data. ”

No MeSH data available.