Public health fears were raised yesterday after around 100 acid-filled tubes washed up on a Cornwall beach.
The beach, at Godrevy Towans, Hayle, was temporarily closed in the morning and the public warned not to open any of the objects that washed-up on the shore.
Police and fire service personnel went to the popular beauty spot after a member of the public handed in a carrier bag full of phials. They uncovered more of the five-inch- long tubes, which have a red metal screw top and contain a clear liquid.
Officers later confirmed the tubes contained a type of casamino acid which is safe when sealed.
They were understood to have been washed-up between Gwithian and Riviera Downs, and the largest amount was recovered from a drum at Mexico beach.
Members of the public were asked to report any further findings to the Coastguard, giving the description and location of any found phials.
It is not known where the phials have come from but officers said they were covered in French writing.
A Cornwall Council spokesman said: "The Health Protection Agency has now confirmed its earlier suggestion that the substance in the glass phials is Triptone, a protein based growing medium used in microbiology.
"This substance is not hazardous and, therefore, does not present a risk to public health.
"The council is continuing to monitor the situation and we are still advising members of the public not to touch the glass phials and to report sightings to the coastguard so they can be removed and disposed of."
A police spokesman said: "Officers have taken advice and believe that the liquid is a type of casamino acid which is safe when sealed but the tube but should not be opened."