Introduction d’entités nouvelles dans la biosphère

• Two main factors have led to chemical pollution being considered a planetary boundary: first, because of its harmful effects on human physiological development and ecosystem functioning; second, because it acts as a slow variable affecting other planetary boundaries. Indeed, chemical pollution can have repercussions on the "biodiversity erosion" boundary by reducing species abundance and potentially increasing organism vulnerability to other threats (climate change). It also interacts with the "climate change" boundary through mercury releases into the environment (via coal combustion) and CO2 emissions from industrial chemicals (petroleum derivatives).

• Setting a threshold for chemical pollution requires understanding the impact of exposure to various substances on organisms and the environment. Given the large quantity of chemicals in circulation, defining a single planetary boundary resulting from the combined effects of these products has not been possible. Two complementary approaches were nonetheless proposed: one focusing on persistent pollutants with global-scale impacts, the other identifying the long-term and large-scale harmful effects of chemical pollution on living organisms.

• During the revision of the conceptual model (Steffen et al., 2015), the boundary's scope, renamed "introduction of novel entities into the biosphere," was redefined. It now applies to new chemical substances, new forms of existing substances, and modified life forms that may have adverse effects on ecosystems, living organisms, and health. The anthropogenic introduction of these entities into the environment is all the more concerning at the global scale given they are persistent, mobile, and spread over large geographic areas. • To this long list of chemical substances are added nanomaterials and plastic polymers mobilized by human activities, which pose risks to human health and the environment. Furthermore, CFC (chlorofluorocarbon) emissions from these novel entities have major effects on the stratospheric ozone layer.

Despite research advances, no analysis has yet made it possible to determine a critical threshold characterizing the boundary as a whole. Prevention actions are being conducted notably through green chemistry. The objective is to better understand and monitor vital planetary processes to detect as quickly as possible the disruptive effects of these novel substances on humans and the environment.

France, through its activities, production and consumption modes, contributes to chemical pollutant releases into the environment. Given the multiplicity of substances and national issues, three types of pollutants are addressed here: marine plastic waste, nuclear waste, and herbicide-tolerant varieties. Other pollution sources covered by this boundary (nanomaterials, endocrine disruptors, etc.) for which France bears responsibility are developed in other parts of the report.

• Plastic, used since the 1950s, represents a major environmental challenge, linked both to resource consumption necessary for its production and waste generation. • Between 1950 and 2017, global plastic production continuously increased, rising from 1.5 million tonnes in 1950 to 350 million tonnes in 2017, or 0.6 kg/capita and 46 kg/capita respectively. In 2015, 15% of global plastic waste is collected for recycling, 25% is incinerated, and 60% is landfilled. According to PlasticsEurope, in France in 2016, of 3.4 million tonnes collected, 22% of plastic waste and 26% of plastic packaging waste are recycled. • Each year, 5 to 13 million tonnes of plastic waste are dumped in the ocean. 80% comes from land and 20% from maritime activities. Land waste sources are diverse: urban waste, tourism, illegal dumping, cosmetics, polyester and acrylic fibers. Half of waste found on European beaches is single-use plastic: bottles, caps, lids, cigarette butts, cotton swabs, chip bags, candy wrappers, sanitary items, plastic bags, utensils, straws, etc. • Plastic waste is dumped in oceans mostly through sewers or rivers. It can also be linked to natural phenomena (storms, tsunamis, floods, etc.). It arrives as macroplastics or microplastics. Microplastics are tiny plastic particles smaller than 5 millimeters. Two categories exist: primary and secondary microplastics. • According to the International Union for Conservation of Nature (IUCN), primary microplastics come from textile degradation (35%), tire wear (28%), urban dust (24%), or were intentionally added to products (wash agents in detergents, exfoliating microbeads in cosmetics, etc.). • Secondary microplastics result from macroplastics spreading in the ocean (via tourism, fishing, ship dismantling industry, etc.) and slowly degrading into small fragments due to marine currents and UV exposure. • Marine pollution from plastic waste has multiple consequences for environment, economy, and health. A "plastic soup" forms in oceans, causing asphyxiation of marine mammals and birds in nets, and also disrupting ecosystem balance through transport of invasive species over long distances, etc. • Microplastics, ingested by many marine organisms (cetaceans, mollusks, plankton, or fish), end up in the food chain. Additionally, plastic contains chemical additives that can be endocrine disruptors. According to IUCN, globally on average 700 marine species are affected, of which 17% are threatened or critically endangered. • Economically, the United Nations Environment Programme (UNEP) estimates the annual cost of plastic waste in oceans at 13 billion dollars in natural capital. Europe's cost represents 470 million euros, according to the European Commission. • Facing these global environmental, economic, and health challenges, UNEP, tasked with evaluating international approaches to combat marine plastic waste, highlights the absence of a dedicated global institution. Only MARPOL (MARine POLlution) exists as an international convention for prevention of ship pollution, which since 1988 has prohibited dumping plastics at sea. • In France, several measures aimed at reducing or eliminating plastic use are in place: the Biodiversity Plan (2018), the law for biodiversity recovery (2016), the energy transition law for green growth (2015), etc. Creation of an EPR system to manage cigarette butts will be studied under the Waste Bill framework in 2019. Finally, in the circular economy roadmap, France aims to recycle 100% of plastic waste by 2025.

• Another national environmental issue: 77% of France's electricity is produced from nuclear plants. France has 13% of operating global nuclear reactors and produces 18% of nuclear-generated electricity. In 2013, just under 1.5 million m3 of radioactive waste exists on French territory, representing one-fifth of global nuclear waste (19%). This volume increased 58% between 2002 and 2016. • Mainly five waste categories exist, classified by storage pathway depending on two criteria: radioactivity level and lifespan. • While very low activity waste and short-lived low and medium activity waste are stored during their radioactive decay period, high activity, long-lived medium activity, and long-lived low activity waste are held awaiting suitable storage facilities. • France accounts for 18% of global high activity waste, or 3,208 m3 conditioned equivalent in 2013. 1.8% comes from foreign countries awaiting shipment. It originates from nuclear industry activities, research, and national defense, consisting of non-recoverable substances from spent fuel reprocessing. Most waste is incorporated into glass then conditioned in stainless steel drums. • France generates 30% of long-lived low and medium activity waste (approximately 135,000 m3 conditioned equivalent in 2013). This waste mainly comes from spent fuel reprocessing and maintenance and operation activities at reprocessing plants. Also included is waste from foreign countries awaiting shipment (2.7% of long-lived medium activity waste). • France contributes 13% of global short-lived low and medium activity waste (approximately 878,000 m3 conditioned equivalent in 2013). This waste mainly originates from maintenance and decommissioning operations of nuclear installations. • Finally, France accounts for 81% of global very low activity waste (approximately 436,000 m3 conditioned equivalent in 2013). This waste type covers waste from operation (rubble, consumables, protective clothing), maintenance, and decommissioning of nuclear installations. France, unlike many countries, does not use a "release threshold" for this waste type, explaining France's large share of these waste. Other countries send this waste to standard treatment pathways (non-nuclear) once waste activity falls below a threshold. • Provisional volumes of French radioactive waste are estimated at 1.8 million m3 in 2020, including 144,100 m3 of high activity and long-lived waste. Estimated 2030 volumes represent 2.5 million m3, including 178,500 m3 of high activity and long-lived waste following ANDRA estimates from 2013 based on waste producer declarations for SR2 scenario (50-year reactor lifespan and nuclear fleet renewal by EPR and fast neutron reactors).

• In France, crop weeding is a decisive factor in agricultural yields. France is Europe's leading herbicide user (nearly 30,000 tonnes sold in 2017). However, to end harmful chemical weeding previously practiced, a new approach emerged in 1996: selection of herbicide-tolerant plant varieties (HTV). • Cultivated plant varieties are obtained through selection for their ability to tolerate application of an existing herbicide substance. They aim to offer farmers a technical response to weeding difficulties. The most widespread HTV globally come from transgenesis; others are obtained through natural variability selection techniques or mutagenesis techniques. • Biotechnology crop commercialization began in 1996 to provide insect resistance or make plants tolerant to herbicides. In France, the only species commercially cultivated is maize (MON810). Since 2008, such crops are prohibited in France due to legislative and regulatory provisions. In 2015, France, like 19 EU member states, obtained exclusion of all or part of its territory from the geographic scope of existing or future cultivation authorizations. • However, this ban applies only to certain techniques (transgenesis) producing GMOs within Directive 2001/18/CE scope. Consequently, mutagenesis and cell fusion techniques used to produce HTV seeds are excluded from this ban. Thus, in 2016, HTV represents 158,000 ha sunflower, or 27% of total sunflower area (versus 144,000 ha and 22% in 2015) and 37,000 ha rapeseed, or 2.6% of total rapeseed area sown in France (versus 17,000 ha and 1.2% in 2015). • Until 2018, HTV obtained through mutagenesis were not subject to European regulations. By ruling of July 25, 2018, the Court of Justice of the European Union considers organisms obtained through mutagenesis to be GMOs under GMO Directive, insofar as mutagenesis techniques and methods modify an organism's genetic material in ways not found in nature. It follows that these organisms fall under GMO Directive scope and are subject to its obligations. • Studies (INRA collective expertise) and experiences in the United States show unreasoned use could lead to herbicide resistance development in weeds and loss of mutation benefits, resulting in increasingly heavy herbicide spraying and environmental impacts. Recommendations to limit these risks concern crop and treatment rotation. Vigilance remains necessary regarding these crop uses.