Detaljerad miljöinformation

Detailed background information

Environmental Risk Classification

Predicted Environmental Concentration (PEC)

PEC is calculated according to the following formula:

PEC (μg/L) = (A*10⁹*(100-R))/(365*P*V*D*100) = 1.5*10^-6*A(100-R)

PEC = 0.000018 μg/L

Where:

A = 0.12 kg (total sold amount API in Sweden year 2016, data from QuintilesIMS).

R = 0 % removal rate (worst case assumption)

P = number of inhabitants in Sweden = 9 *10⁶

V (L/day) = volume of wastewater per capita and day = 200 (ECHA default) (Ref. I)

D = factor for dilution of waste water by surface water flow = 10 (ECHA default) (Ref. I)

Predicted No Effect Concentration (PNEC)

Ecotoxicological studies

Blue-green algae (Anabaena flos-aquae) (OECD 201) (Ref. II):

EC₅₀ 72 h (growth) = 0.31 mg/L

EC₅₀ 72 h (yield) = 0.14 mg/L

NOEC 72 h (growth rate and yield) = 0.063 mg/L

Crustacean, water flea (Daphnia magna) (OECD 211) (Ref. III):

Chronic toxicity

NOEC 21 d (survival and reproduction) = 0.6 mg/L

Fish, fathead minnow (Pimephales promelas) (OECD 210) (Ref. IV):

Chronic toxicity

NOEC 32 d (embryo hatching success and larval survival) = 0.03 mg/L

PNEC = 3 μg/L (30 µg/L / 10 based on the most sensitive chronic NOEC for the fathead minnow and an assessment factor (AF) of 10)

Environmental risk classification (PEC/PNEC ratio)

PEC/PNEC = 0.000018/3 = 0.000006, i.e. PEC/PNEC ≤ 0.1 which justifies the phrase "Use of tedizolid phosphate has been considered to result in insignificant environmental risk."

Degradation

Biotic degradation

Degradability (OECD 308) (Ref. V):

The biodegradation of [¹⁴C]tedizolid was studied for 100 days in two aerobic sediments varying in pH, textural characteristics, organic matter content and microbial content with associated overlying waters. Water/sediment samples from each system were analyzed at 2, 15, 29, 43, 64 and 100 days after dosing.

No evidence of primary or cumulative biodegradation was observed. The half-life of [¹⁴C]tedizolid is greater than 100 days.

Justification of chosen degradation phrase:

The DT50 for the total system was >120 d; therefore the phrase “The substance is potentially persistent” is chosen.

Bioaccumulation

Partitioning coefficient (OECD 117) (Ref. VI):

Log K_ow = 1.3 (HPLC)

Justification of chosen bioaccumulation phrase:

Since log K_ow < 4 the substance has low potential for bioaccumulation.

References

1. ECHA, European Chemicals Agency. 2008 Guidance on information requirements and chemical safety assessment. http://guidance.echa.europa.eu/docs/guidance_document/information_requirements_en.htm

2. Dr. U. Noack - Laboratorien, 2012. "BAY 1170438: Alga, Growth Inhibition Test with Anabaena sp (Anabaena flos-aquae), 72 hours," Project No. 120705BL, Germany, 20 December 2012.

3. Bayer, 2014. "Reproduction study of BAY 1170438 (Tedizolid) in Daphnia magna," Report No. PH-37511, Bayer HealthCare, 13 January 2014.

4. Bayer, 2013. "Early-Life-Stage-Test Fish with Tedizolid (BAY 1170438)," Report No. PH-37546, Bayer HealthCare, 17 December 2013.

5. Bayer, 2013. "Aerobic Transformation in an Aquatic Sediment-System with Tedizolid [BAY 1170438 (C14)]," Report No. PH-37547, Bayer HealthCare, 25 November 2013.

6. Bayer, 2012. "Tedizolid / BAY 1170438 / Physicochemical Report / Determination of the Partition Coefficient (n-Octanol/Water), HPLC Method," No. 12100009, Bayer HealthCare, 09 October 2012.