Sustainability of artificial turf pitches under investigation

Due to weath­er con­di­tions, hard, ash and nat­ur­al grass pitch­es are not always playable. Arti­fi­cial turf, on the oth­er hand, can be used all year round, mak­ing it a pop­u­lar and wide­spread sur­face. How­ev­er, this is accom­pa­nied by neg­a­tive envi­ron­men­tal impacts. This is shown by a sys­tem analy­sis of arti­fi­cial turf pitch­es, which Fraun­hofer UMSICHT has now pub­lished in a report. The report iden­ti­fies top­ics such as the release of microplas­tics, recy­cling or site selec­tion and at the same time pro­vides rec­om­men­da­tions on how those respon­si­ble can take coun­ter­mea­sures and make arti­fi­cial turf fields more sustainable.

The FSB trade fair for open space, sports and exer­cise facil­i­ties will be held in Cologne from Octo­ber 26 to 29, 2021. Sports fields and thus also arti­fi­cial turf fields will play an impor­tant role there. The lat­ter in par­tic­u­lar have enor­mous rel­e­vance in this coun­try, as they enable sports to be played out­doors all year round. This is also reflect­ed in the sys­tem analy­sis of Fraun­hofer UMSICHT, which was com­mis­sioned by var­i­ous munic­i­pal­i­ties and com­pa­nies, in that it spec­i­fies an aver­age usage time of 1882 hours per field and year. Accord­ing to the analy­sis, clay pitch­es, i.e. hard or ash pitch­es, on the oth­er hand, are no longer con­sid­ered to be up to date by both the clubs and the play­ers. They have been increas­ing­ly con­vert­ed in recent years — most­ly into arti­fi­cial turf pitches.

“Com­mon arti­fi­cial turf pitch­es, how­ev­er, are asso­ci­at­ed with neg­a­tive envi­ron­men­tal impacts. Emis­sions from these pitch­es have become the focus of soci­ety, pol­i­tics and the media in the con­text of the debate about microplastics.”

- Juer­gen Bertling

A team of sci­en­tists* stud­ied a total of 19 arti­fi­cial turf pitch­es in Ger­many and Switzer­land. Based on analy­ses, data col­lec­tion and sur­veys, the pub­lished report describes and eval­u­ates the cur­rent sta­tus and makes rec­om­men­da­tions for more sus­tain­able sports field con­struc­tion. The report address­es the plan­ners and man­u­fac­tur­ers as well as the oper­a­tors and users.

Almost 3 tons of material lost per pitch per year

To pos­i­tive­ly influ­ence play­ing per­for­mance, a so-called infill is applied to arti­fi­cial turf pitch­es. In the major­i­ty of the pitch­es exam­ined, this con­sists of sand and a rub­ber gran­u­late. Unin­filled pitch­es and those with the nat­ur­al mate­r­i­al cork are cur­rent­ly the exception.

Obser­va­tions show that espe­cial­ly dur­ing heavy rain or wind, the infill gets into the sur­round­ing area, where it col­lects or even ends up in bod­ies of water, for exam­ple. In addi­tion to weath­er-relat­ed emis­sions, clean­ing activ­i­ties such as snow shov­el­ing and the play­ers them­selves have a major influ­ence on mate­r­i­al dis­charge: they take the mate­r­i­al with them in their shoes and on their cloth­ing. On aver­age, the exper­i­men­tal­ly deter­mined annu­al loss of the arti­fi­cial turf fields stud­ied can be put at 2.98 tons of infill per year. “Syn­thet­ic fibers, which also wear out dur­ing the use of a pitch, have not yet been tak­en into account here,” adds Jür­gen Bertling. More detailed stud­ies are need­ed here, he says, to clar­i­fy whether the loss­es actu­al­ly reach rel­e­vant quan­ti­ties. Even after the study, it remains unclear through which path­ways and in what quan­ti­ties the loss­es of infill and fibers reach the soils and water bodies.

Anoth­er impor­tant aspect of the sys­tem analy­sis is the con­sid­er­a­tion of the CO2 foot­prints of arti­fi­cial turf pitch­es. Depend­ing on the pitch type, these range from 9.4 to 29.8 kg of car­bon diox­ide equivalent[1] per hour of use. By way of com­par­i­son, this is sig­nif­i­cant­ly less than dri­ving a car for an hour or swim­ming in an indoor or out­door pool.

Great potential for improved environmental protection

The sys­tem analy­sis shows that the envi­ron­men­tal impact of an arti­fi­cial turf pitch depends to a large extent on the choice of mate­ri­als, struc­tur­al inte­gra­tion and recy­cling at the end of its life cycle. The experts see great poten­tial here — start­ing with the use of a more sus­tain­able mate­r­i­al for the sub­struc­ture and infill, through the use of rain­wa­ter for irri­ga­tion, to the fil­ter­ing of fines. Bar­ri­ers sur­round­ing the site would addi­tion­al­ly reduce microplas­tic emis­sions into the envi­ron­ment. “We also address the issue of loca­tion. After all, it makes a big dif­fer­ence whether an arti­fi­cial turf pitch is locat­ed in an urban envi­ron­ment or, say, in a val­ley sur­round­ed by nature. In the future, more atten­tion should be paid to a clever choice of loca­tion with regard to nature con­ser­va­tion, but also with regard to the fre­quen­cy of use by play­ers and thus the need for a pitch,” says Jür­gen Bertling. And last but not least, the reg­u­la­to­ry side must also be con­sid­ered as a steer­ing instru­ment, for exam­ple by revis­ing norms or cre­at­ing new standards.

Majority of players want more environmentally friendly artificial turf pitches

Both active and for­mer play­ers are very involved in the debate on the rel­e­vance and envi­ron­men­tal impact of arti­fi­cial turf pitch­es. The major­i­ty of those sur­veyed as part of the sys­tem analy­sis sup­port the state­ment that the pitch­es need to become more sus­tain­able. Although rub­ber gran­ules are still pre­ferred as the infill type, peo­ple are def­i­nite­ly open to more envi­ron­men­tal­ly friend­ly alternatives.

Accord­ing to the sci­en­tists, these are good con­di­tions for achiev­ing a com­pro­mise between inten­sive use of the pitch and a min­i­mum neg­a­tive impact on the environment.