It is Friday evening and you are relaxing and enjoying a glass or two of a ten year old red wine. You roll the wine on your tongue and you detect a bouquet of raspberry and leather with a slight hint of phthalate. Hang on, what is phthalate? There shouldn’t be any phthalates in wine, should it? It is bad enough to have the sulfite preservative in the wine if you belong to the 5-10% of the population that is allergic to sulfite. But phthalates are hormone disrupting chemicals added to plastics to increase their flexibility and durability. They are considered carcinogenic, mutagenic and reprotoxic by the European Chemicals Agency. They don’t belong in wine, so what’s the story here?
Chinese consumer vigilance
Let’s go back a couple of years to 2012 and China. Following the catastrophic melamine-contamination scandal of 2008, Chinese consumers started to worry about other possible contamination problems. Thus, when elevated levels of phthalates were found in leading Chinese baijiu brands in November 2012, it caused a dramatic slump in sales. Baijiu is a popular white spirit produced from sorghum with 40-60% alcohol. Chinese authorities immediately lowered allowable phthalate levels in alcoholic drinks and clamped down on the maximum levels permitted in all wines and spirits. In March 2013, Chinese customs impounded containers of French wine and cognac on suspicion that they might contain phthalates. And they did, causing a flurry of testing, with laboratories in South West France suddenly swamped with samples from anxious exporters.
You may remember a previous scare regarding phthalates in cling film or glad wrap in the 1990s. They were found to migrate easily to fatty food products like cheese and meat. Studies suggested that phthalates might be a factor in some cases of breast cancer, asthma, diabetes and attention deficit hyperactivity disorder in children. It is a group of chemicals that provoke universal anxiety, since they are now almost everywhere from household dust to the nasogastric tubes and surgical gloves used in hospitals.
New study quantifying the problem
Now a new study published in Food Additives and Contaminants provide some clarity of the extent of the problem of phthalates in a variety of French wines and spirits. The research showed that 59% of the wines analysed contained significant quantities of one particular form of phthalate, known as dibutyl phthalate, and only 17% did not contain any detectable quantity of at least one of the reprotoxic phthalates. Perhaps a more worrying statistic is that 11% of the wines analysed did not comply with EU specific migration limits (SML) for materials in contact with food, the only regulation applicable since no specific limits for phthalates in wine have yet been set in Europe.
So what is the origin of the phthalates in wine? The study analysed a variety of materials frequently present in wineries and found phthalates in winery equipment, especially tank linings, plastic vessels used in racking processes, the plastic tubing used to pump must or wine from one vessel to another, and pump components themselves. And ethanol as a solvent is a perfect way of extracting phthalates from plastics. That, of course, is why spirit producers need to be particularly vigilant.
As it happened, the French government stepped in to reassure consumers that this was an administrative issue and nothing to do with dangerous contaminant levels, adding that the change in the Chinese legislation affected tens of wine and spirit shipments from Bordeaux, Spain and Argentina, not only Cognac.
Should you be worried?
This might be an issue of limited toxicological impact in the overall scheme of things with so many other potential sources of phthalate exposure. More expensive wines aged in oak barrels might carry less risk. Australian wines have so far not been implicated in the contamination scare so there might be ample choices available to still enjoy a glass or two of wine on Friday evening.