Rid­ding the sea and land from tox­ic plastics fragments

Plastic products made of PVC, Poly­styrene and oth­er prom­in­ent plastics are flood­ing the mar­ket. They are a grow­ing threat to the envir­on­ment, as they are found in the sea or dumped in land fills. But in a few years, there may be ways of tack­ling this wor­ry­ing trend. BioClean, an EU-sponsored research pro­ject, due to be com­pleted in 2015, is spar­ing no effort to find ways of redu­cing the impact of non-bio­de­grad­able plastics in the envir­on­ment. In 2012, the world­wide plastics pro­duc­tion was 288 mil­lion tons. More than 95% was due to poly­mer­ic mater­i­als, plastics, obtained from fossil resources. Europe alone con­trib­uted for about 20% of the glob­al pro­duc­tion. Cur­rently, the chem­ic­als are dis­posed of through land filling, incin­er­at­ing and recyc­ling. The trouble is that plastic waste in land­fills often under­goes photo oxid­a­tion, a type of oxid­a­tion due to dir­ect sol­ar radi­ation, and degrad­a­tion. As a res­ult, small frag­ments and particles, which can absorb tox­ins and tox­ic chem­ic­als, are released in the envir­on­ment. These particles may even­tu­ally be inges­ted by mar­ine anim­als, thus enter­ing the food chain. In this con­text, the pro­ject strategy aims at gain­ing a deep­er sci­entif­ic under­stand­ing of bio­de­grad­a­tion of such mater­i­als in nat­ur­al envir­on­ments and waste dis­pos­ing facil­it­ies. It also explores the feas­ib­il­ity of bio­tech­no­lo­gic­al solu­tions for an effect­ive and sus­tain­able dis­pos­al of plastic waste. Spe­cific­ally, the pro­ject is focused on four kinds of plastics: PVC, Poly­styrene, Polypro­pyl­ene and Poly­ethyl­ene. Pro­gress is already in sight. ​“So far, we have iden­ti­fied more than 15 bac­teri­al cul­tures along with some ter­restri­al fungi — about ten strains — that are able to degrade at least one of the four tar­get chem­ic­als,” says Fabio Fava, pro­fess­or of indus­tri­al and envir­on­ment­al bio­tech­no­logy at the Uni­ver­sity of Bologna, Italy. ​“This means that we have a num­ber of new microbes cap­able of degrad­ing fossil based plastics,” says Fava, who is also the pro­ject coordin­at­or. How­ever, he adds: ​“the bio­de­grad­a­tion observed is often slow and lim­ited.” To make the plastic more amen­able to bio­de­grad­a­tion the research­ers have used a range of pre-treat­ments such as UV and gamma rays as well as ozone irra­di­ation. ​“This has res­ul­ted in encour­aging res­ults”, says Fava. The pro­ject research­ers are now integ­rat­ing the pre-treat­ment pro­cesses with the bio­de­grad­a­tion to see how one can make the plastics less harm­ful to the envir­on­ment. Ulti­mately, the aim is to devel­op a com­bin­a­tion of phys­ic­al, chem­ic­al and bio­tech­no­lo­gic­al pro­cesses for the bio­de­grad­a­tion and detox­i­fic­a­tion of plastic waste in exist­ing land­fills. The pro­ject may also pro­mote bio­de­grad­a­tion of plastic frag­ments and particles gen­er­ated in waste com­post­ing, import­antly, plastics that is found in mar­ine hab­it­ats. This work has so far been very well received among sci­ent­ists work­ing with bio­de­grad­a­tion of plastics. ​“As far as I can judge, the con­sor­ti­um is engaged in very import­ant tests that can play a decis­ive role in mak­ing plastic products less harm­ful to the envir­on­ment,” says Ms Minna Hakkarain­en lead­er at KTH, the Roy­al Insti­tute of Tech­no­logy in Stock­holm, Sweden, con­duct­ing a research pro­ject on design­ing bio­de­grad­able plastics. Mean­while, envir­on­ment­al organ­isa­tions wel­come the focus of this work in pre­vent­ing harm­ful plastics enter­ing the sea. ​“All efforts that can be made to pre­vent and mit­ig­ate the cur­rent impact of plastics in mar­ine eco­sys­tems should be wel­comed,” says Stephan Lut­ter, inter­na­tion­al mar­ine policy expert at WWF Ger­many in Ham­burg, con­clud­ing: ​“How­ever, it’s clearly a dif­fi­cult work, and it will take quite some time until pro­gress can be made.” Source: your​is​.com