Assessing the Discharge of Pharmaceuticals Along the Dutch Coast of the North Sea - Reviews of Environmental Contamination and Toxicology - page 13

Schrap et al. (2003) report removal efficiencies of 8-12%, 48-67%, and 6-63%
for sotalol, diclofenac, and azitromycin, respectively. No data on removal rates of
roxitromycin, during sewage-water treatment, were found in literature.
All other pharmaceuticals listed in Table 1 show a net addition of pharmaceu-
ticals in the Netherlands. The amount of bezafibrate sold in the Netherlands, in
1999 (Derksen et al. 2001), agrees with the net addition of bezafibrate in 2002
(Table 1).
Table 1 shows that analgesics are by far the most highly consumed (sold) phar-
maceuticals in 1999. However, the only analgesics in the top 20 (Table 1) are
diclofenac and ibuprofen. Paracetamol does not appear among the top 20, although
223 t was sold in the Netherlands in 1999. The low discharge rate of paracetamol
to the DCZ (0.32 t yr −1 in 2002) is caused by the high removal efficiency of
paracetamol in Dutch STPs. Schrap et al. (2003) reported 100% removal percentages
for paracetamol. Fent et al. (2006) also reported total removal of paracetamol by
STPs. Although less ibuprofen and diclofenac are sold than paracetamol (Table 1),
more of these pharmaceuticals are discharged to the DCZ as a result of the lower
STP removal percentage of these pharmaceuticals (52-96% and 48-67% for ibupro-
fen and diclofenac, respectively) (Schrap et al. 2003).

3.3 Pharmaceuticals Versus OSPAR Priority Substances

Mandatory monitoring of the following chemical substances was initiated in 2002
as a result of the framework of the OSPAR convention for the protection of the
marine environment of the North Sea: total Hg (mercury), total Cd (cadmium), total
Cu (copper), total Zn (zinc), total Pb (lead), lindane, ammonia, expressed as N,
nitrates, expressed as N, orthophosphates, expressed as P, total N, and total P. PCBs
(polychlorinated biphenyls) were measured on a voluntary basis. The discharge
data of ten pharmaceuticals to the DCZ in 2002, as estimated in this study, are
together with the OSPAR priority substances presented in Table 2.
Table 2 shows that the discharge of the pharmaceuticals iopromide, carbamazepine,
diatrizoic acid, iopamidol, iomeprol, syulfamethoxazol, sotalol, iohexol, diclofenac,
and metoprolol to the DCZ is in the same order of magnitude as the discharge of
the mandatory OSPAR substances Cd and Hg. The discharge of the listed pharma-
ceuticals is an order of magnitude larger than that of the recommended OSPAR
substance PCBs, and two orders of magnitude larger than lindane (mandatory
monitoring).

3.4 Environmental Impact of Discharged Pharmaceuticals

Among pharmaceuticals discharged in significant amounts to the DCZ are those
that have human and ecotoxicological risks that are largely unknown (Jørgenson