posted on 2019-08-01, 12:38authored byMafalda Castro, Anna Sobek, Bo Yuan, Magnus Breitholtz
Chlorinated
paraffins (CPs) are industrial chemicals, subdivided
into three categories: short chain (SCCPs), medium chain (MCCPs),
and long chain (LCCPs) chlorinated paraffins. SCCPs are currently
restricted in Europe and North America. MC and LCCPs are being used
as substitution products, but there is a knowledge gap concerning
their bioaccumulation potential in aquatic organisms. In this work,
we performed laboratory bioconcentration (passive uptake) and bioaccumulation
(including dietary uptake) experiments with Daphnia magna using five different CP technical substances. All tested CP technical
substances were bioaccumulative in D. magna, with
log BCF and log BAF values ranging between 6.7–7.0 and 6.5–7.0
(L kg lipid–1), respectively. An increase in carbon
chain length and an increase in chlorine content (% w/w) of the CP
technical substances had significant positive effects on the log BCF
and log BAF values. For the different CP technical substances, 50%
depuration was achieved after 2 to 10 h when D. magna were transferred to clean media. Our results show that SC, MC, and
LCCPs are (very)bioaccumulative in aquatic organisms. We believe these
data can aid the ongoing policy discussion concerning the environmental
risk posed by CPs.