I have some pieces of flat roof that are covered with bitumen. This often gives off a brownish color. Is it safe to use this water for the irrigation of fruit and vegetables or is this not recommended due to the possible presence of toxins?
Answer
Normally yes. If the water is not collected on the roofing roof itself, the contact time with the water is too short to exchange many leakable components with the water.
A bottom of water must have been in contact with the roofing for a long time to have exchanged so many leakable components that it would be unhealthy for consumption.
More components are probably absorbed in the water from the plastic barrel or garden hose that the water comes into contact with than from the bitumen on the roof.
In addition, keep in mind that the water is also partially filtered through the soil before it is absorbed by the vegetables.
Answered by
drs. Karel Haesevoets
Chemistry Electrochemistry Physics
Old Market 13 3000 Leuven
https://www.kuleuven.be/
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