Thin Layer Chromatography used to clear fish in India
The fishing ban put in place after an oil tanker collision off 
the coast of India has been lifted after Thin Layer Chromatography tests on 138 samples revealed no trace of oil.
Here's excerpts from the Hindustan Times:
On August 10, three days after the collision, the Brihanmumbai Municipal Corporation had taken 138 samples of local varieties of fish such as mandeli, red prawns and Bombay duck from 30 civic markets and tested them.
The Thin Layer Chromatography (TLC) test on these samples, conducted at the National Institute of Oceanography and a private institute, showed no traces of oil. “No trace of oil has been found on any of the samples. But fish-eaters should be cautious,” said Deepak Kamat, assistant municipal commissioner, markets department.
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