Presentation is loading. Please wait.

Presentation is loading. Please wait.

Janet F. Bornman Co-Chair, Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol Curtin University Perth, Western Australia 6845

Similar presentations


Presentation on theme: "Janet F. Bornman Co-Chair, Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol Curtin University Perth, Western Australia 6845"— Presentation transcript:

1 Janet F. Bornman Co-Chair, Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol Curtin University Perth, Western Australia 6845 Janet.Bornman@Curtin.edu.au 1 Workshop on Hydrofluorocarbon (HFC) Management Montreal Protocol Paris, 11-12 July 2014

2 Hydrochlorofluorocarbons (HCFCs) Ozone Depleting Substances (ODS) Greenhouse Gases (GHGs) Hydrofluorocarbons (HFC) Greenhouse Gases (GHGs) 2 The effect of HFC and HCFCs on the biosphere Do they have an effect on the biosphere?

3 UV-generated hydroxyl radicals (  OH), determine the atmospheric lifetime of climate-relevant compounds including: HFCs, HCFCs, CO, NOx, and SO 2, methane …. 3 The effect of HFC and HCFCs on the biosphere Levels of complexity UV radiation, ozone, climate, health, environment HCFCs enter the body by inhalation of air, or by skin contact: breathing difficulties, skin irritation, may affect other internal organs

4 Ground-level O 3, aerosols UV NOx Volatile organic compounds Premature mortality (annual, global) ~1.5 million from particulate matter (sulfate, nitrate, most organic aerosols) ~0.5 million from O 3 (OECD, 2013) Agricultural losses of $12-21 billion (Avnery et al., 2011) Complex sensitivity to UV radiation and climate Air quality and UV radiation

5 Documented: Effects of decreased O 3 and increased UV radiation Not yet well documented: How will the environment/biosphere be affected by increased O 3 and decreased UV radiation? And how will climate interactions modify the response? 5 Predicted likely decrease in tropospheric  OH Lower OH implies slower removal of many important gases: HFCs, HCFCs, other VOCs, methane, NOx, SO 2 Ozone and climate implications

6 Trifluoroacetic acid (TFA), a breakdown product of HCFCs and HFCs in the atmosphere Readily deposits to the Earth’s surface through dry and wet deposition Some of the new hydrofluoroolefins (HFO, unsaturated HFCs) as replacements for HFCs can lead to increases in TFA (HFO TFA) 6 The effect of HFC and HCFCs on the biosphere

7 Salt lakes with no outflow, loss by evaporation only Microbiological degradation in soil and water TFA HFCs, HFOs, and HCFCs CF 3 -CX y H O CF 3 -C-OH O CF 2 Cl-C-OH Strong acid, forms salts with minerals in soil Concentrations in flowing water are small Accumulation will occur in salt lakes, playas and in the ocean TFA - Environments at risk 7

8 8 The effect of HFC and HCFCs on the biosphere Trifluoroacetic acid (TFA) Phytotoxic - negative effects on plant growth But concentrations not sufficient for observed effects

9 Time (days) -100102030405060 Length of watermilfoil (cm) 0 5 10 15 20 25 30 35 Control 100 μg/L 1,000 μg/L 30,00 μg/L 10,000 μg/L No significant effects on plants, even at high concentrations 9 TFA and TCA Contro l

10 10 The effect of HFC and HCFCs on the biosphere Trifluoroacetic acid (TFA) Phytotoxic - negative effects on plant growth But concentrations not sufficient for observed effects Anthropogenic sources Atmospheric degradation of some HCFC and HFCs Atmospheric degradation of narcotics Trifluoromethyl containing pesticides, aluminum production Natural sources Underwater hydrothermal vents (?)

11 11 Approximate concentrations of TFA Switzerland, Fresh water lakes, springs, rivers: ca 100 ng/L USA, Fresh water lakes, springs, rivers: 20 – 140 ng/L Europe, Rain water: 0 - 1.5 µg/L Oceans: 10 – 200 ng/L Depositions of TFA largest during the growing seasons

12 Summary HCFC has potential negative health effects TFA is not bioaccumulative Risks to mammals, including humans, aquatic and terrestrial organisms: negligible TFA sources (natural and anthropogenic) and cycling through the biosphere should be considered for their environmental impacts Continuing monitoring of TFA in the environment may be required if HFOs are significantly increased to replace HFCs 12

13 Summary WMO Assessment of Ozone Depletion (2007): “TFA from the degradation of HCFCs and HFCs will not result in environmental concentrations capable of significant ecosystem damage.” 13


Download ppt "Janet F. Bornman Co-Chair, Environmental Effects Assessment Panel (EEAP) of the Montreal Protocol Curtin University Perth, Western Australia 6845"

Similar presentations


Ads by Google