Green stuff on walls and floor of basement

Hi, need some help. I notice in the basement today, there is a lot of green stuff on the wallls and floor. It's my first time seeing this. Images link below, thank you.

Can anyone tell me what this is?
is it dangerous to health?
and how to get rid?

https://ibb.co/BKQLK9S
https://ibb.co/8BYd6Sk
https://ibb.co/2ZGvmyF

Thank you

Asked by Steven on 5th Jun 2023
Expert Trade Answers
"If you have trees close by it could be algae or moss try washing it down with bleach then fresh water and it should kill it and keep it clean. Rob"
Answered on 8th Jun 2023 - Member since Jan 2023 - report
"Looks to me like you have a problem with air flow/ventilation and this definitely is bad for you to breath into your lungs and definitely needs looked at immediately ."
Answered on 22nd Jun 2023 - Member since Jun 2023 - report
"It sounds like damp..you need to find out where all the water is coming from.might be a good idea to get someone in to damp proof the wall it will only get worse and can be bad for health"
Answered on 11th Jun 2023 - Member since Apr 2018 - report
"Could be mould and algy as the underground basment could be damp so maybe air vents will help"
Answered on 5th Jul 2023 - Member since Jul 2022 - report
"It is most likely mould caused by damp which is hazardous to health, your basement most likely needs waterproofing or tanking."
Answered on 11th Jun 2023 - Member since May 2023 - report
"Hi I have had a look at the pictures,it looks like rising damp which is coming up through the floor but would need to have a look to confirm this."
Answered on 5th Jun 2023 - Member since Sep 2020 - report
"That is damp. It's a good solution to find where it is exactly coming water. Because if you clean that using Zinzer and painting that. After that will coming again. That brick is sucked a lot of water. Maybe need to paint floor with floor-paint, isolate that damp. But need to see that. Thanks. If any questions let me know. Any time to help Jay."
Answered on 5th Jun 2023 - Member since Sep 2022 - report
"This is or could be mould. Bright green mould is a form of fungi that grows in a shade of green. This could be dangerous to health. Please get this inspected ASAP!"
Answered on 6th Jun 2023 - Member since Jun 2023 - report
"Green residue is generally when the earth abutting the basement walls is leaching through the masonry. I suspect you do not have a tanking system.

The immediate solution should be to apply a strong anti mould bleach. Please wear a suitable FFP3 mask and rubber gloves. If there is a window, open the window. Plenty of fresh air after application.

Let the bleach work its magic for 15mins and wipe with disposable rags or paper towels. Dispose of paper towels. Apply second round of bleach and repeat the step.

Mould from saturated walls is never good for a healthy home. There are several health risks, the main one is respiratory issues.

Should the mould persist, please consult a waterproofing professional."
Answered on 15th Jun 2023 - Member since Jun 2023 - report
"It sounds like green mold, it's usually as a result of poor ventilation, It's not good for people especially with underlying illness or breathing difficulties. You can remove small areas with home remedies. Baking soda – Hydrogen peroxide – Vinegar. This can be done regularly to keep it at bay.
If it's serious I’d get someone in."
Answered on 16th Jun 2023 - Member since May 2023 - report
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