White foam on rainwater 'is normal'

Experts draw up emergency plan but say pollution levels are safe so far

Thunderstorms on Tuesday morning made the Tianjin recovery operation more difficult, with an increased risk of rainwater becoming polluted. However, the air and water quality were still within what is considered a safe range, monitoring officials said.

The first rainfall after the massive blasts on Aug 12 has prompted fears that remaining hazardous chemicals at the site may pollute the water and then contaminate surrounding areas, which would be a danger to public health.