Health warning: toxic caterpillars in summer

The Hague’s Public Health Department (GGD) often issues a health advisory in the summer months when caterpillars on the beach shed toxic hairs.

Caterpillar nest by a cycle path. Photo by
Caterpillar nest by a cycle path. Photo by

The brown-tail larvae (bastaardsatijnrups) and oak processionary larvae (eikenprocessierups) can pose a risk to human health. The caterpillars are covered in irritating hairs which contain a toxin and contact with these hairs can cause health problems. Both types of caterpillars are often spotted in the dunes and on the beaches between Kijkduin and Scheveningen.

Caterpillar hairs can cause health problems if they come into contact with skin, leading to rashes, skin irritation, headaches and breathing difficulties.

Health complaints

The caterpillars are found in dune plants such as sea-buckthorns but they are also found on the beach. People can have health complaints even if they haven’t come in direct contact with the caterpillar. The caterpillar hairs break off as barbs and can be carried by the wind and get into skin or clothing. Animals can also experience health problems if they come into contact with the hairs.

Avoid direct contact

The GGD Den Haag has issued the following advice:

  • Avoid any contact with the caterpillars.
  • Wear clothing which covers your body.
  • Avoid contact with nests and cocoons in the dunes.

If you do come into contact with the caterpillar hairs, the GGD advises you not to scratch or rub the affected area but to wash or rinse the skin or eyes with water. In the event of serious health complaints, contact your general practitioner. Complaints usually go away within 2 weeks.

More info

For more information, you can contact The Hague's Public Health Department (GGD Den Haag), afdeling Leefomgeving at tel. (070) 353 71 82 (Monday to Friday).

Published: 5 March 2012Modified: 22 June 2018