Determination of Major and Trace Metals in Date Palm Fruit (Phoenix dactylifera) Samples Using Flame Atomic Absorption Spectrometry and Assessment of the Associated Public Health Risks

Table 3

Optimization of time for the digestion of 0.5 g of the date palm fruit samples at a constant volume and digestion temperature.

Reagent volume ratio (HNO3 : HClO4)	Temperature (°C)	Digestion time (hrs)	Results (solution color)
3 : 1	300	0.50	Light yellow
3 : 1	300	1 : 30	Slightly yellow
3 : 1	300	2 : 00	Colorless with turbid
3 : 1	300	2 : 30	Slightly yellow
3 : 1	300	3 : 00	Clear and colorless solution