Given the visible growth and the presence of a toddler, a professional inspection is strongly advised. The humid Dubai climate causes condensation issues in AC units, and hidden mold within the ductwork or behind walls is common. A proper inspection involves moisture meters and often air or surface sampling sent to a microbiology lab to identify the species, which determines the health risk and required remediation scope.

For your health concerns, black spots from chronic water damage can indicate Stachybotrys or other problematic species, which are known to cause respiratory irritation and exacerbate allergies. This is particularly important for young children. Do not attempt to clean it yourself, as disturbing the mold can release a high concentration of spores into the air you breathe.

Your first step is to document everything with photos and send a dated written notice to the landlord or property management company, referencing the AC leak and mold growth. They are typically obligated to arrange and pay for the inspection and repairs. If they are unresponsive, you can escalate the matter to the Rental Dispute Center (RDC) in Dubai.