The maximum allowable limit for cadmium is 0.2 ppb/day. The spectrophotometric quantitation of cadmium in drinking water can be performed using a complexation reaction. Cadmium(II) (Cd2+) makes a deep greenish-yellow complex (1:1 mole ratio) with alizarin red S. The extinction coefficient of the complex is 2.24×103 L•mol−1•cm−1 at 422 nm. Given that most spectrophotometers cannot detect absorbances less than 0.0001 with good reliability, is this method a good way to quantify cadmium at its allowable limit in drinking water? Assume a cell path length of 1.0 cm.