International trade can affect the environment in different ways. This may justify the introduction of border measures by the importing countries. In addition to various dispositions in the GATT, GATS, TRIPs agreements, as well as in the Agreement on Agriculture, this issue is regulated by the agreements on Technical Barriers to Trade (TBT) and on the application of Sanitary and Phyto-sanitary standards (SPS). Despite these rules, abuse of environmental arguments for protectionist reasons remains an open issue. In order to disentangle protectionism from dispositions justified on the grounds of true environmental concerns, we systematically review notifications of SPS and TBTs by importing countries at the tariff line level. Trade is considered as being potentially affected when an environmental SPS/TBT is notified on grounds of environmental concerns. Affected trade is defined as imports by countries notifying such barriers. Protectionist use of environmental barriers is likely when only a limited number of countries impose an environmental obstacle on the imports of a given product. Considering data for 2001, we find that 88 per cent of the value of world trade is in products potentially affected by such measures, while 39 per cent of the value of world imports is potentially subject to a protectionist use of such measures. Agriculture, the automobile industry, the pharmaceutical industry and many other sectors are concerned.