Erin Brockovich investigates mystery of 15 girls at same school suddenly developing Tourettes

Mystery surrounds a mass outbreak at a school that has led to 15 girls developing a Tourette Syndrome-style illness, with symptoms including twitching and involuntary swearing.

Doctors are baffled as to why the girls at Le Roy High School have fallen victim to the ailment over the past few months, reports Sky News.

One theory is that the symptoms could be due to conversion disorder - once known as mass hysteria.

Even though it is a psychological condition, the symptoms are real.

Campaigner and environmentalist Erin Brockovich is now investigating whether it could have something to do with pollution.

Ms Brockovich - whose life was depicted in a film starring Julia Roberts - is looking into whether a chemical that spilled in a 1970 train derailment about four miles from the school could have anything to do with it.

Although the school has ruled out a link with the derailment because "the plume has been shown moving in the opposite direction some three miles away", it has called in an independent environmental expert to investigate.

School administrator Kim Cox said the school wants "sound advice" from professionals on the situation, "void of self-interest".

"Our community has suddenly found itself at the centre of national attention due to the students who have been exhibiting neurological symptoms," he said in a statement.

"This has led to much speculation, conjecture and misinformation in the national media and consequently within our community."

According to the Mayo Clinic, females are much more likely to get conversion disorder and it is more common in adolescents or young adults.