The Health Board took a water sample on July 23.
The water results showed a very high amount of Escherichia coli bacteria and five times more intestinal bacteria than allowed.
Tiia Luht said: "These results are very bad and concerning."
She added that this indicates significant pollution. Pollution can cause skin rashes, eye infections, and stomach viruses in people.
Children, elderly, and people with weakened health may become more seriously ill.
The Health Board states that illnesses have arisen not only from swimming but also from playing in the sand.
Therefore, it is necessary to wash hands after playing in the sand and before eating.
The Health Board recommends avoiding swimming areas if the water is cloudy, green, dirty, has an unpleasant odor, or if there is a sewage system nearby.
Inglirand is not an official swimming beach, but many people still go there.