Moulds are microscopic fungi. Provided they find dampness conducive to their growth and sufficient nutrients, they can colonise various kinds of media: wood, paper, cloth, food products, etc.
Moulds can release in air:
• spores in large amounts
• odorants (musty smell)
• toxic substances (mycotoxins, volatile organic compounds).
Of environmental origin, mould spores are introduced inside the premises:
• through openings;
• the comings and goings of occupants;
• their clothes and shoes;
• dust and contaminated materials/equipment.
Dampness generally favours the growth of most moulds, although there are species of mould adapted to conditions of drought.
Places conducive to the growth of mould are:
• humid rooms (bathroom, etc.) poorly ventilated rooms
• bottom of poorly insulated walls or walls with leaks
Their growth on contaminated media results in patches of various sizes and colours (green, grey, black, etc.).
Moulds can cause:
• allergic reactions and irritation of mucous membranes, in sensitized individuals;
• pulmonary infection (invasive aspergillosis) in people with impaired immune systems;
• hypersensitivity pneumonitis, as part of professional activities (agriculture, dairy), where massive amount of spores is inhaled.
Some tips to limit the growth of moulds!
• Ventilate after performing activities that produce a lot of dampness (bath, shower, cooking, etc.) to avoid permanent condensation on the surfaces (walls, furniture, etc.).