Updated: Jul 16, 2021
Worldwide epidemic of allergic contact dermatitis from MI, which is replacing parabens in products
A review study in the journal Dermatitis (Nov.-Dec. 2015; 26(6):254-259), suggests that the biocides being used to replace parabens in cosmetic products are causing multiple cases of allergic contact sensitization.
Dr. Denis Sasseville, the lead author of the study, said concerns about parabens began when an article called “Underarm cosmetics are a cause of breast cancer” was published in the European Journal of Cancer Prevention (2001; 10:389-393).
“Just above [the title of Dr. Philippa Darbre’s 2001] paper there was the word ‘hypothe-sis’, but of course the media did not [note] this, they just used the title itself,” said Dr. Sasseville, director of the contact dermatitis clinic at the Montreal General Hospital and professor in the Faculty of Medicine at McGill University Health Centre.
“And [the paper] eventually became viral on the Internet and all the groups that are pro-nature and against everything chemical just got on to that [bandwagon].”
In her 2001 article, Dr. Darbre suggested that because parabens are endocrine disruptors they could stimulate breast cancer, particularly because deodorants and other underarm cosmetics are applied close to the breast.
“[In 2004 Dr. Darbre published a study] analyzing the contents of some breast tumours and she did find some parabens—except that her methodology was completely flawed,” said Dr. Sasseville. “Because she had about 20 samples of breast cancer and she divided those samples into six groups and for each group that she analyzed for the presence of paraben she did one blank, a sample where there was no tumour, and she found parabens even in the blanks where there should not be.
“[When] her paper was criticized for poor methodology, she replied by saying that it could have been contamination in the lab by the technicians who were wearing perfumes or products. If your data is contaminated you do not publish. But it was published anyway” (Appl Toxicol 2004; 24:5–13).
Parabens have low estrogenic activity
Dr. Sasseville and his colleagues, in their article, found that Dr. Darbre is partly correct. “Yes, parabens have mild estrogenic activity, but it is very low—10,000 times less than the natural estrogen that [females produce],” he said. “Most toxicologists who have reviewed parabens have agreed with our findings [that parabens are safe] because they say the amount is so low, parabens are rapidly metabolized, and they do not really accumulate in tissues for very long.”
He continued, “Yes you can find them in tissues because there is penetration in the skin. Dr. Darbre did not test other tissues to see if parabens were there, and of course finding parabens in . . . [a] sample of breast cancer does not mean that [parabens] caused [the cancer].”
The rate of allergic contact dermatitis to parabens is only about 1%, according to a study Dr. Sasseville published with international colleagues that tested 4,238 patients (Dermatitis Jan-Feb 2015; 26(1):49-59).
This compares to a rate of about 5% (risk ratios [RRs]: 2.01 [1.60-2.52], 1.87 [1.61-2.18]) for methylchloroisothiazolinone/methylisothiazolinone (MCI/MI).
“You cannot go anywhere without seeing ‘this product is paraben free’. And why? Because they contain MI, they contain formaldehyde-reducers . . . and there are newer preservatives that will be arising on the market pretty soon that have already been responsible for cases of allergic reactions.”
MI causing worldwide epidemic of ACD
“Right now we are trying to deal with a worldwide epidemic of allergic contact dermatitis from MI, which is now replacing parabens in many products,” said Dr. Sasseville. “You cannot go anywhere without seeing ‘this product is paraben free’. And why? Because they contain MI, they contain formaldehyde-reducers . . . and there are newer preservatives that will be arising on the market pretty soon that have already been responsible for cases of allergic reactions.”
Dr. Sasseville said of all the preservatives, in terms of contact allergy, parabens are the safest and have been in use for the longest period of time, since the 1930s. Parabens are esters of a natural product, p-hydroxybenzoic acid, which is present in blueberries, coconuts, vanilla, green tea, and other foods.
Replacements for parabens worse in terms of contact allergy
“The pharmaceutical industry should try to refrain from jumping on [the no paraben] bandwagon, but they have no choice because that is what the popu-lation is asking for,” he said. “They want the products that do not contain those ‘nasty parabens’ but they are not aware that what the industry is replacing them with is worse in terms of contact allergy. They find out when they do get allergic reactions that sometimes are pretty nasty and severe.”
He said the MI epidemic is more serious than just allergic contact reactions from cosmetics because MI is being used in industrial products such as paints, glues, and varnishes in much higher concentrations than they are in cosmetic products.
“There have been cases where patients have become allergic from MI from exposure to cosmetics and then they decide to paint their house and they develop an airborne contact dermatitis, which is some-times very severe. There have been people who have had to stay away from their house for weeks before the paint was dry enough so that they could re-enter their house.”
Cosmetic companies are becoming aware of the contact dermatitis problem with MI, according to Dr. Sasseville, and are beginning to remove it from their products, though they will not go back to using parabens because “the damage is already done.”
New preservatives on market have caused contact reactions
“They are introducing newer preservatives one is called iodopropynyl butyl-carbamate and the newest one that is just coming is polyaminopropyl biguanide. We will see those two becoming allergens in the next decade,” he said.
Dr. Sasseville noted that some companies are developing tubes of creams and lotions where the lid is one way, which reduces bacterial contamination and the need for preservatives. Others, he said, are looking at single use packets—though the generated waste may be harmful to the environment.
Dr. Sasseville concluded that it is important for dermatologists to publish articles and to speak out publicly to set the record straight about parabens and to warn about harmful preservatives such as MI.
Article originally published in The Chronicle of Skin & Allergy (Mar. 2016; 22(2):10,16)