Melanoma is the deadliest form of skin cancer, but it is also one of the most preventable, according to the Canadian Cancer Society.

It is important to keep tabs on what you’re smearing and spraying onto your skin in an effort to prevent cancer, says a U.S. public health watchdog.  

The non-profit Environmental Working Group has released its guide to the safest, most effective sunscreens on the market, in its eighth annual report on the subject.

“We started because we realized there were no clear rules governing the use, marketing and formulation of sunscreen in the United States," senior EWG analyst Sonya Lunder said. "And as a result we were seeing some really misleading and unsafe products on the market.”

The EWG looks at active and inactive ingredients in sunscreen, rates formulations for their ability to protect skin from UVA and UVB rays, looks at stability of ingredients and checks for allergens and potentially dangerous chemicals.

Once all that data has been analyzed, products are classified on a rating system from zero, or low hazard, to 10, or high hazard. 

“In our opinion there are some ingredients that are pretty widely used in sunscreens that we’re concerned about or think shouldn’t be in [it],” Lunder said.

Know what's coating your skin

Coppertone ranking

The EWG ranked this product in its high hazard category, because some of its ingredients may actually increase the chance of skin damage when exposed to UV radiation. (EWG)

A common ingredient the EWG is wary of is retinyl palmitate, a form of vitamin A added to sunscreen as an antioxidant.

“Federally funded research found that when you add this form of vitamin A to a skin cream and then put it on mice and expose them to UV radiation, they have higher rates of skin damage, skin tumours and lesions," Lunder said. "And this is because the ingredient breaks down to a phototoxic ingredient that’s harmful to the skin.”

Lunder says an early draft of Health Canada’s sunscreen monograph was going to require a warning against this and other anti-aging ingredients, with specific recommendations. 

“When you use this product, you need to avoid the sun and you may be more sensitive to sunburn for up to a week afterward," she said. "And we found when we looked at the final rules that were passed last summer, that language had been removed."

Lunder said there are some easy tips to keep in mind when shopping for a safe, effective sunscreen, and suggested the first step is to avoid sunscreen packaged in an aerosol spray can.

“The FDA has raised concerns here in the U.S. that these sunscreens may not coat your skin thick enough to provide adequate sun protection. And that’s another issue: people spray and it’s hard to keep track of where you’re spraying and it’s uncommon for people to spray enough on.”

Health Canada’s sunscreen monograph has specific recommendations for spray products as well, which include, “Do not apply in windy conditions, use in a well-ventilated area and avoid inhaling.” 

Badger

Badger sunscreen earned a low hazard ranking from the Environmental Working Group's 2014 sunscreen guide. (Badger)

 

Lunder also explained that Canada no longer permits SPF labels of higher than 50, though products in the U.S. are often labelled as having SPF values of 51 up to 110. She said higher SPF values offer a false sense of security, so users don't reapply often enough or use enough of the product initially. 

She also said to avoid buying sunscreen and bug spray packaged as one product. 

“It’s an issue because often in the summer when you’re outdoors you need both. But the problem is that for sunscreen, you need to be reapplying every two hours and for bug spray that may not be necessary."