Water pollution levels in China were more than twice the government’s official estimate in 2007, according to the country’s first national census on pollution sources, Reuters reported. The census found that chemical oxygen demand (COD) in wastewater was 30.3 million metric tons. This conflicts with information released two years ago, which suggested that 2007 was the first year water pollution in China fell, with COD declining 3% to 13.8 million metric tons. The disparity, blamed on a failure to include agricultural waste in calculations, calls into question the validity of Chinese official statistics as well as the effectiveness of Beijing’s push for cleaner growth. Zhang Lijun, the vice environmental protection minister, sought to play down the issue, saying the scope of data used in the census was much wider. Other data weren’t so suspicious. The census put sulfur dioxide emissions at 23.2 million metric tons, while earlier estimates settled on 24.7 million metric tons. Activists welcomed the government efforts to assess pollution problems, but asked to see detailed results.