The multinational drug company AstraZeneca has a long-standing commitment to proactively manage the environmental risks associated with drug manufacture and products in patient use (see Nature 526, 164; 2015). In the absence of legislation to control discharges from production sites, we have voluntarily devised concentration limits to ensure the safety of aquatic environments.

These environmental reference concentrations and maximum tolerable concentrations are derived using approaches similar to environmental quality standards developed under the Water Framework Directive (R. J. Murray-Smith et al. Integr. Envir. Assess. Manag. 8, 320–330; 2012). We have established them for all 42 of the company's active pharmaceutical ingredients.

Our global manufacturing sites and our key outsourced manufacturing partners meet these safe-discharge criteria. This should help to raise environmental standards across the industry. We completed 72 assessments of environmental reference concentrations with our supply chain in 2014.

We continuously collate published environmental data on all of our active pharmaceutical ingredients to keep our risk assessments and safe-discharge standards scientifically up to date (G. Holm et al. Drug Safety 36, 533–546; 2013).