Now Foods fish oil concentrate is manufactured under strict quality control standards. It is tested for potentially harmful levels of contaminants such as PCBs, dioxins, mercury and other heavy metals. From the FDA: "Supportive but not conclusive research shows that consumption of EPA and DHA omega-3 fatty acids may reduce the risk of coronary heart disease." The Global Organization of EPA and DHA Omega-3s (GOED) recently completed its 2022 Randomized Testing Program NOWs Molecularly Distilled Omega-3 was found to be compliant with the GOED Voluntary Monograph quality parameters.