Last week, scientists reported on two developments surrounding our use of plastics. New health concerns have arisen with some of our traditional plastics, but other advancements are leading to greener and cheaper biodegradable plastics. Thank goodness!
First, the challenging news. A study published in the journal Hypertension details new concerns with two chemicals commonly used to manufacture plastic wrap, cosmetics, soap, and food containers. These compounds, abbreviated as DINP and DIDP, are part of a group of chemicals known as phthalates (pronounced "THAL-ates").
The data in this study comes from a large ongoing clinical trial that involves thousands of volunteers. By looking at urine samples and other measurements in a subset of 1329 children and adolescents, researchers found a link between concentrations of phthalates and higher blood pressure. And only two months ago, the same researchers published a paper in The Journal of Clinical Endrocrinology & Metabolism which described a link between phthalate exposure and increased insulin resistance, an indicator for the development of diabetes.
"Our research adds to growing concerns that environmental chemicals might be independent contributors to insulin resistance, elevated blood pressure and other metabolic disorders," reported Leonardo Trasande, MD, MPP, a professor at NYU Langone and the lead investigator of these studies.
Disturbingly, over the last decade, manufacturers have increasingly switched to using DINP and DIDP because of similar concerns with another phthalate, DEHP. Trasande added that "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 (the 1976 Toxic Substances Control Act)." Yes, that does sound like a good idea, now doesn't it!
In addition to cosmetic products and food containers, phthalates are found in plastic containers with recycling numbers 3, 6 or 7. These can include food wraps, detergent and shampoo bottles, egg cartons, meat trays, disposable plates and cups. According to Trasande, "alternatives to DIDP and DINP include wax paper and aluminum wrap; indeed, a dietary intervention that introduced fresh foods that were not canned or packaged in plastic reduced phthalate metabolites substantially."
Fortunately, at the same time, there are other researchers working to improve biodegradable plastics, so that hopefully we can rely less on these traditional, petroleum-based plastics. One type of biodegradable plastic, polylactic acid (PLA), is manufactured from corn and sugarcane and is compostable, if it is handled properly. PLA can be used to make food containers and wraps, but its higher production price has limited its widespread use.
So, it is with great delight, that we report on another study published last week in the journal Science. This paper, by a research team in Belgium, details a cheaper and even greener method for manufacturing PLA. Using a novel chemical approach, the researchers were able to simplify the production process and remove wasteful chemical steps. According to Michiel Dusselier, lead author of the paper and a postdoctoral researcher at KU Leuven, "our new method has several advantages compared to the traditional technique: we produce more PLA with less waste and without using metals. In addition, the production process is cheaper, because we can skip a step.”
The researchers report that the patent for this method has already been sold to a chemical company, suggesting that plans are underway to get these products out to consumers. Hopefully we will soon have access to a cheaper, greener alternative to traditional plastics.