The summer holidays are in full swing and without school many children will have time on their hands - time they might use joining in with harmful video challenges.

Internet Matters, a not-for-profit organisation supported by BT, has highlighted six challenges being shared online which children might feel pressured to join in with but which have potentially dangerous consequences.

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As well as causing physical harm, the challenges promote think like bullying, the sharing of inappropriate images and even suicide.

Parents may think their children won’t get involved in the challenges, but Internet Matters ambassador and psychologist Dr Linda Papadopoulos says that mums and dads should never underestimate the peer pressure faced by children.

“It’s important parents don’t bury their heads in the sand and assume their children would never take part in one of these challenges,” she warns.

“These are just some of the most severe games that have been cropping up, but there might be a number of manifestations so at the very least they will form the trigger to begin a conversation with your child.

“We know that children will be desperately wanting to engage online with their school social group during the holidays as they are not seeing them every day, which will be coupled with a desire to take part and the fear of missing out. Of course, this is completely natural, but parents can take responsibility to make sure they’re doing this safely.

 “We’d urge parents to have a simple one-to-one conversation with their child about these types of challenges and give them practical advice on what to do if they encounter anything like this, the risks involved and the consequences.”

Here are six of the online challenges parents should guard against this summer:

The Blue Whale Challenge

What is it?  Teenagers follow a series of accounts on social media that assigns them tasks - 50 challenges over 50 days. Challenges start with things like watching a horror film, but get more extreme to include self-harm and, on the 50th day, goading them to commit suicide.

Some question whether the challenge is a hoax, but images on social media suggest it could be genuine. Reports have claimed it is responsible for the death of over 130 children in Eastern Europe and parents of two US teenagers have also blamed the challenge for their children’s suicides.

Instagram is now issuing a warning message to users if they search for the ‘suicide dare game’ and directs them to seek help from the Samaritans.

What issues does this present? Risk of self-harm, viewing inappropriate content, creating inappropriate content.

What’s the advice? Internet Matters advises: Parents need to talk to their children about online trends among their peers and chat to them regularly about what games their friends are talking about. Talk to them about how they may face peer pressure online as they would offline. Ensure that you have set up their device safely to stop your child being able to find self-harm websites and images. If you are worried about your child’s emotional welfare or are concerned they may have come across The Blue Whale Challenge contact the Samaritans on 116 123.

The Deodorant Challenge

What is it? In this challenge, children film themselves spraying deodorants as close to their skin as is bearable to see who can tolerate the pain the longest. The challenge has left some children with bad burns.

What issues could this raise? Peer pressure, physical injury.

How can I help prevent this? Internet Matters advises: Have a conversation with your child and find out if they have heard of the challenge or know of anyone who has taken part. Talk to them about peer pressure. Remind them of the physical damage it can cause to their body and have a sensible conversation about the emotional damage posting something like this can have on them, especially when they’re older, as the physical scars may never fade.

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The Pass Out Challenge/Space Monkey/Choking Game

What is it? Teen are filmed deliberately passing out with the aim of reaching a high. It was deemed responsible for several deaths including that of Karnel Haughton, 12, of Birmingham, who lost consciousness and died after apparently playing the ‘choking game’ in June 2016.

In June 2017, head teacher Paul Ramsey of Verulam School in Hertfordshire told how he was forced to hold an assembly about the worrying online game as he discovered pupils were attempting to copy it from videos they had seen on social media.

What issue does this raise? Physical injury, sharing of inappropriate content.

How do I help prevent this? Internet Matters advises: Have a conversation with your child before they are given access to social media about dangerous trends and urge them to talk to you or a trusted adult should they hear about or see any. Talk to your child in a relaxed setting so they don’t feel they are being interrogated such as in the car. Look for signs of the challenge including bruises on their neck or bloodshot eyes. If you have concerns that your child’s school friends may be taking part in a dangerous trend, contact your child’s school and raise awareness of the issue.

Salt & Ice Challenge

What is it? In this craze teenagers are filmed putting salt on their skin and then placing an ice cube on top of it. The aim is to see who can bear the pain the longest: the temperature of the ice drops when it gets into contact with the salt and can go as low as -26C, resulting in burns like frostbite in some teens.

Earlier this year, the NSPCC issued a warning to parents to remain vigilant over the Salt and Ice Challenge.

What issues does this raise? Peer pressure, physical injury

How can I address this? Internet Matters advises: Ask your child if they know anyone who has taken part in the salt and ice challenge or if it’s something they have heard of. Talk to them about peer pressure and how to say ‘no’. Discuss the dangers of posting inappropriate videos online and remind them that if something is posted online, it can be difficult to get it removed.

[Read more: Online gaming  - keep your children safe online]

Snapchat Streaks

What is it?  Snapchat is a photo-sharing social network used by many young people. A Snapstreak is when pictures are sent back and forth between two Snapchatters for a consecutive number of days - the aim is to get as high a Snapstreak as possible. Send 100 snaps to each other and your streak count will be 100. Once you receive a snap, you must send one back within 24 hours, or restart. Teenagers are using Snapstreaks as a way of measuring friendship – a low Snapstreak means they aren’t good friends with the other person.

What issues could this raise? Parents have complained it has led to cyberbullying when their child was responsible for losing the Snapstreak, as well as excessive screen time.

How can I help prevent this? Internet Matters advises:Talk to your child about relationships and reiterate that popularity cannot be measured by an arbitrary number and remind them an app should not be responsible for their self-esteem or determine who their real friends are. If you have concerns about cyberbullying visit Internet Matters.

The Touch My Body Challenge

What is it? In this challenge one person is blindfolded while a second player forces them to touch a part of their body. Players can be obliged to touch another person’s private body parts. The challenge is filmed and shared across social media.

What issue does this raise? Sharing of inappropriate content.

How can I help prevent this? Internet Matters advises: Talk to your child about the game and ask them if they have ever seen any Touch My Body Challenges or have ever been asked to take part. This may seem like a difficult conversation to have, so chose neutral ground or somewhere you both feel comfortable before broaching the subject.

Reiterate once something is online, it’s extremely difficult to get removed. Urge your child to apply the ‘T-shirt test’ when it comes to sharing images, pictures or videos to friends. Would you wear it on your T-shirt? If not, then don’t send it.

Explicit content can spread very quickly over the internet and will affect your child’s reputation at school and in their community both now and in the future. It could also affect their education and future employment prospects.

For a comprehensive and easy-to-use resource of the most up-to-date information for keeping your child safe online, check out Internet Matters.