Determination of Very Low Level of Free Formaldehyde in Liquid Detergents and Cosmetic Products Using Photoluminescence Method

Table 7

Tolerable concentrations of foreign species for determination of 1 × 10⁻⁶ M formaldehyde.

Foreign ion	Tolerable concentration (M)	Tolerable limit ((species)/(HCOH))	Relative error (%)
Na^+,		100000	−2.7
Mg^2+		1000	4.1
Ca^2+		1000	−3.8
Benzaldehyde		1000	−2.3
Propionaldehyde		500	2.6
Acetaldehyde		500	2.9
Ni^2+		100	3.6
Pb^2+		100	−3.8
Cd^2+		100	4.1
Fe^+3		50	2.7