In a study published in the journal Hypertension, researchers from the NYU Langone Medical Center discovered that chemicals used to manufacture plastic products are no better for the health than the chemical they replaced to make plastic use safer.
The compounds di-isodecyl phthalate (DIDP) and di-isononyl phthalate (DINP) are chemicals used to replace di-2-ethylhexyphthalate (DEHP) after it was shown to have adverse effects on health. However, researchers were able to show that DIDP and DINP are also bad for the health even when they are being used as supposedly safer alternatives to DEHP. According to Leonardo Trasande, lead investigator for the study, their research adds to the growing number of studies pointing to chemicals as contributors to higher blood pressure levels, elevated insulin resistance and other metabolic disorders.
Specifically, Trasande and colleagues found that DIDP and DINP are associated with higher blood pressure levels. For each time that phthalates are consumed tenfold, a 1.1-millimeter increase in mercury was recorded in blood pressure.
In an earlier study, Trasande and his colleagues also unveiled an association between DIDP and DINP and increased insulin resistance, which increases risks of diabetes. According to the results of that research, one in every three adolescents with the highest levels of DINP in their system also had the highest level of insulin resistance. On the other hand, one out of four of those with low concentrations of the chemicals in their bodies experienced insulin resistance.
For this new study, the researchers used information from the National Health and Nutrition Examination Survey and took blood samples from 356 individuals aged between 12 and 19 to evaluate for the presence of phthalates. Urine and blood samples were once again collected from 2008 and 2012 and blood pressure levels were taken.
"Our study adds further concern for the need to test chemicals for toxicity prior to their broad and widespread use, which is not required under current federal law," Trasande added.
DEHP was banned in Europe in 2004 after it was found to be detrimental to the health. The United States followed suit, with manufacturers voluntarily replacing the chemical with DIDP and DINP over the last 10 years. Trasande's research linking hypertension and exposure to DEHP in Americans came out in 2013.
To limit phthalate exposure, food must not be covered with plastic wrap or microwaved in plastic containers. If plastic use cannot be altogether avoided, people can stick with plastic containers not labeled with the numbers 3, 6 and 7 (inside the symbol for recycling) as these indicate phthalate content.
Photo: Alex Shultz | Flickr