The T-value in the score for hazard refers to acute toxicity. Underlying data for P, B and T are based on previous environmental information on Fass.se. Environmental information is missing on fass.se (2018-10-09). It is voluntary for manufacturers to provide information about environmental impact on fass.se.
Pivmecillinam is an inactive "prodrug" that is rapidly hydrolyzed to its active form, mecillinam. Measurements in the environment or in wastewater are lacking in mecillinam, even internationally.
When selecting the algal test for antibiotics the European Medicines Agency, EMA, recommends test on blue-green algae (cyanobacteria).
Fass environmental information for Selexid (pivmecillinam), downloaded 2011-03-08.
Persistence: "Mecillinam is not readily biodegradable (OECD biodegration test, reference: B. Halling-Soerensen et al. 2000)."
Bioaccumulation: log Kow = 0.70 +/- 0.38.
Acute toxicity: There is data for 3 trophic levels, lowest cyanobacteria (M. aeruginosa) 60 microg/L.
PEC/PNEC is based on sales data in Sweden in year 2008. PEC/PNEC = 0.11 which gives the risk low.
Pivmecillinam is expected to have low environmental risk for aquatic organisms and low risk of resistance selection in wastewater. However, there is a risk of additive effect with other beta-lactam antibiotics.
Ciprofloxin is present in Swedish watewater treatment plants in concentrations that are likely to select for antibiotic resistance. Risks associated with large emissions of ciprofloxacin to the environment in manufacturing abroad have been detected. Ciprofloxacin is considered to be of greater environmental risk than pivmecillinam.
Nitrofurantoin is considered to be of even less risk to the environment than pivmecillinam.
Comparative assessment of environmental risk and risk of resistance selection in the environment using trimethoprim and pivmecillinam in Sweden (Report Goodpoint 2018).From a resistance-selection-risk perspective in wastewater treatment plants, pivmecillinam appears to be a slightly better alternative than trimethoprim.
For antibiotics in general, it is recommended that these drugs are used as restrictively as possible without risking the patient's health.
Author: The Pharmaceutical unit of Region Stockholm