Nitrate (NO3-) as N, 1000µg/mL in Water, 100ml

Arsenic, 1000ug/ml, 100ml

As @ 1000 µg/mL in 5% HNO3, 100ml

Method 200.8/1638/1640 Internal Standard, 10µg/ml in 2%-HNO3, 4x25ml