**6.11 Plastic particles**

Plastics may reveal partition coefficients of PBDEs of several orders of magnitude higher than those towards sewage sludge or soil at levels of 0.04–1.6 w% [66, 67]. In detail, accumulation of PBDEs in low density polyethylene films (LDPE), an adequate and commonly accepted model for diffusive transport phenomena across biomembranes, showed accumulation factors against the aqueous phase (KPEW) of 105 –107 in case of 23 BDE congeners covering the total spectrum of bromination [68]. Furthermore, a curvilinear correlation between the log KPEW and log KOW factor, very similar to the correlation of BCF and log KOW shown in **Figure 1** was observed and explained by energy barriers for diffusive transport into the LDPE structure [68]. The statement of rising KPEW levels at higher lipophilicity of BDE congeners was further confirmed [67]. However, KPEW levels are strongly affected

### **Figure 1.**

*Correlation of log KOW and log BCF of 25 BDEs of high environmental relevance (*−*3,* −*7,* −*17,* −*28,* −*30,* −*47,*  −*49,* −*66,* −*85,* −*99,* −*100,* −*123,* −*153,* −*154,* −*155,* −*183,* −*184,* −*191,* −*197,* −*201,* −*202,* −*206,* −*207,* −*208,*  −*209) applying simple mathematical models with/without correction.*

by the type of plastic and the temperature level during test conditions as adsorption is an endothermic process. While enhanced accumulation of BDE congeners was observed for polyethylene, polypropylene, polystyrene, and polyamide, low accumulation levels were observed for polyvinylchloride [66–68]. Hence, the hypothetical potential of injection of plastic particles into the soil as sink for PBDE and thereby soil remediation was positively investigated.
