Some 85 percent of 952 sunscreens tested are ineffective or contain potentially harmful chemicals, says this year’s annual sunscreen review by the Environmental Working Group. Of 144 sunscreen products distributed by the top three leading brands — Coppertone, Banana Boat, and Neutrogena — only one meets EWG’s criteria for safety and efficacy. The group raises especial alarm about common ingredient oxybenzone, which a handful of animal studies have linked to endocrine disruption. Some dermatologists accuse EWG’s sun-protection rating system of lacking scientific rigor, but the group says it extensively reviewed medical literature on sunscreens and stands behind its data. If you’re rushing out to buy one of the 28 sunscreens that fall under both the Effective and Low Hazard rubric, buy a hat too — dermatologists stress that sunscreen without other sun-avoidance precautions may not have much of an effect on skin cancer.