Organisers behind the Bramham Park-based festival have warned attendees of a rise in MDMA-related deaths, and a rise in potent pills being identified across the UK at festivals this summer.
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"In 2005 each pill contained around 80mg of MDMA. Some recent pills have tested upwards of 250mg MDMA. This could be firmly in the fatal overdose range.
"A combination of factors are at play such as body weight, hormone levels, mixing with other drugs including alcohol, underlying health, and so on. There is no safe dose."
The festival also confirmed there would be welfare and first aid tents onsite that attendees should head to if they begin to feel unwell: "You could save your friend’s life. People who are overdosing can go downhill very quickly so don’t delay in seeking help," a statement on Leeds Festival's website reads.
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At the end of the warning, the festival gives out advice to those attending regarding drug use. Leeds reminds consumers that low price does not imply weakness, that purity does not imply safety, and that a dose can be increased but never decreased.
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Read the full drugs warning statement from Leeds Festival here.
Aneesa Ahmed is Mixmag's Digital Intern, follow her on Twitter