These residues can pose serious health risks, especially for vulnerable groups such as children, the elderly, or those with compromised immune systems. Meth Testing New Zealand helps property owners, tenants, and buyers identify if a home or building has meth residue so that steps can be taken to decontaminate it if necessary. These residues can pose serious health risks, especially for vulnerable groups such as children, the elderly, or those with compromised immune systems. Meth Testing New Zealand helps property owners, tenants, and buyers identify if a home or building has meth residue so that steps can be taken to decontaminate it if necessary.