Environmental Pawprint of Dogs as a Contributor to Climate Change
Simple Summary
Abstract
1. Introduction
2. Materials and Methods
- (1)
- Composition of dog feces and dietary factors affecting their properties;
- (2)
- Fertilizer potential of dog feces;
- (3)
- Environmental impact of dog feces;
- (4)
- Overlooked emission pathways in companion animal systems, including packaging, plastics, and hygiene products;
- (5)
- Strategies for reducing emissions from dog excreta.
3. Results
3.1. Composition of Dog Feces and Dietary Factors Affecting Their Properties
3.2. The Fertilizer Potential of Dog Feces and Challenges of Composting
3.3. Environmental Impact of Dog Feces: Nitrogen Compound Emissions
3.3.1. Ammonia and Nitrous Oxide Emissions
3.3.2. NOx and VOCs—Underestimated Sources of Urban Emissions?
3.4. Phosphorus—The Underestimated Component of Dog Feces and Its Environmental Consequences
3.5. Overlooked Emission Pathways in Companion Animal Systems: Packaging, Plastics, and Hygiene Products
3.6. Strategies for Reducing Emissions from Dog Excreta
- Dietary functional additives, including probiotic bacteria (e.g., Bacillus, Lactobacillus), prebiotics, symbiotic formulations, enzymes (e.g., proteases), plant extracts (e.g., piperine), and mixtures of organic acids [61].
- Proper manure management, such as timely removal from housing environments and adequate storage conditions. Additives like biochar have also been tested to reduce emissions from stockpiled manure [62].
4. Conclusions
Funding
Data Availability Statement
Conflicts of Interest
References
- Treves, A.; Bonacic, C. Humanity’s dual response to dogs and wolves. Trends Ecol. Evol. 2016, 31, 489–491. [Google Scholar] [CrossRef]
- Cowan, N.; Brownlie, W.; Tomlinson, S.; Carnell, E.; Drewer, J.; Dragosits, U.; Spears, B.M. A global assessment of nitrogen and phosphorus generated in the waste streams of domesticated cats and dogs. Sustain. Environ. 2024, 10, 2415181. [Google Scholar] [CrossRef]
- Bryce, C.M. Dogs as pets and pests: Global patterns of canine abundance, activity, and health. Integr. Comp. Biol. 2021, 61, 154–165. [Google Scholar] [CrossRef]
- European Pet Food Industry Federation. Available online: https://europeanpetfood.org/ (accessed on 25 September 2025).
- Okin, G.S. Environmental impacts of food consumption by dogs and cats. PLoS ONE 2017, 12, e0181301. [Google Scholar] [CrossRef]
- Zabielski, R.; Zarzyńska, J. Jaki jest udział zwierząt towarzyszących w zmianie klimatu? Życie Wet. 2024, 99, 412–415. [Google Scholar]
- Yavor, K.M.; Lehmann, A.; Finkbeiner, M. Environmental Impacts of a Pet Dog: An LCA Case Study. Sustainability 2020, 12, 3394. [Google Scholar] [CrossRef]
- Arksey, H.; O’Malley, L. Scoping studies: Towards a methodological framework. Int. J. Soc. Res. Methodol. 2005, 8, 19–32. [Google Scholar] [CrossRef]
- Hu, L.; Huang, X.; Liu, S.; Fang, L.; Zhang, J.; Tang, X. The impact of carbohydrate quality on gut health: Insights from the NHANES. PLoS ONE 2025, 20, e0315795. [Google Scholar] [CrossRef]
- Paßlack, N.; Theis, L.V.; Vahjen, W.; Zentek, J. Effects of the protein concentration and quality in a canned diet on the fecal microbiota of healthy adult cats. Metabolites 2022, 12, 105. [Google Scholar] [CrossRef] [PubMed]
- He, W.; Connolly, E.D.; Wu, G. Characteristics of the digestive tract of dogs and cats. In Nutrition and Metabolism of Dogs and Cats; Wu, G., Ed.; Springer: Cham, Switzerland, 2024; Volume 1446, pp. 15–33. [Google Scholar] [CrossRef]
- Martínez-Sabater, E.; García-Muñoz, M.; Bonete, P.; Rodriguez, M.; Sánchez-García, F.B.; Pérez-Murcia, M.D.; Bustamante, M.A.; López-Lluch, D.B.; Moral, R. Comprehensive management of dog faeces: Composting versus anaerobic digestion. J. Environ. Manag. 2019, 231, 109437. [Google Scholar] [CrossRef]
- Wood, C.W.; Cummins, K.A.; Williams, C.C.; Wood, B.H. Impact of diet and age on element excretion from dogs. Commun. Soil Sci. Plant Anal. 2004, 35, 1263–1270. [Google Scholar] [CrossRef]
- De Frenne, P.; Cougnon, M.; Janssens, G.P.J.; Vangansbeke, P. Nutrient fertilization by dogs in peri-urban ecosystems. Ecol. Solut. Evid. 2022, 3, 12128. [Google Scholar] [CrossRef]
- Paradeis, B.; Lovas, S.; Aipperspach, A.; Kazmierczak, A.; Boche, M.; He, Y.; Corrigan, P.; Chambers, K.; Gao, Y.; Norland, J.; et al. Dog-park soils: Concentration and distribution of urine-borne constituents. Urban Ecosyst. 2013, 16, 351–365. [Google Scholar] [CrossRef]
- de Molenaar, J.G.; Jonkers, D.A. De Invloed van Stikstof in de Ontlasting van Honden op de Vegetatie in Voedselarme Bos-en Natuurterreinen (No. 038); IBN-DLO: Wageningen, The Netherlands, 1993. [Google Scholar]
- Axelsson, E.; Ratnakumar, A.; Arendt, M.L.; Maqbool, K.; Webster, M.T.; Perloski, M.; Liberg, O.; Arnemo, J.M.; Hedhammar, Å.; Lindblad-Toh, K. The genomic signature of dog domestication reveals adaptation to a starch-rich diet. Nature 2013, 495, 360–364. [Google Scholar] [CrossRef]
- Tazerji, S.S.; Elahinia, A.; Akhtardanesh, B.; Kabir, F.; Vazir, B.; Duarte, P.M.; Hajipour, P.; Rehman, A.; Ilyas, M.F.; Hassanzadeh, S.; et al. Nutritional risks and consequences of meat-only diets for dogs and cats. Ger. J. Vet. Res. 2024, 4, 62–76. [Google Scholar] [CrossRef]
- Marx, F.R.; Trevizan, L.; Saad, F.M.O.B.; Lisenko, K.G.; Reis, J.S.; Kessler, A.M. Endogenous fat loss and true total tract digestibility of poultry fat in adult dogs. J. Anim. Sci. 2017, 95, 2928–2935. [Google Scholar] [CrossRef]
- Fahey, G.C.; Flickinger, E.A.; Grieshop, C.M.; Swanson, K.S. The role of dietary fibre in companion animal nutrition. In Dietary Fibre: Bio-Active Carbohydrates for Food and Feed; Brill: Wageningen, The Netherlands, 2023; pp. 295–328. [Google Scholar] [CrossRef]
- Rayne, N.; Aula, L. Livestock manure and the impacts on soil health: A review. Soil Syst. 2020, 4, 64. [Google Scholar] [CrossRef]
- Aladjadjiyan, A. (Ed.) Agricultural Waste and Residues; InTech: Rijeka, Croatia, 2018. [Google Scholar] [CrossRef]
- Wuthisuthimethavee, S.; Prempramote, J.; Boonhoh, W.; Promwee, A.; Hayakijkosol, O.; Wongtawan, T. Do Not Throw Pet Faeces Away: Composted Manures Obtained from Dog and Cat Faeces Contain High Nutrients and Effectively Cultivate Plants. Recycling 2024, 9, 123. [Google Scholar] [CrossRef]
- Zhou, J.M. The effect of different C/N ratios on the composting of pig manure and edible fungus residue with rice bran. Compost Sci. Util. 2016, 25, 120–129. [Google Scholar] [CrossRef]
- Shen, B.; Zheng, L.; Zheng, X.; Yang, Y.; Xiao, D.; Wang, Y.; Sheng, Z.; Ai, B. Insights from meta-analysis on carbon to nitrogen ratios in aerobic composting of agricultural residues. Bioresour. Technol. 2024, 413, 131416. [Google Scholar] [CrossRef]
- Nemiroff, L.; Patterson, J. Design, testing and implementation of a large-scale urban dog waste composting program. Compost Sci. Util. 2007, 15, 237–242. [Google Scholar] [CrossRef]
- Bernal, M.P.; Alburquerque, J.A.; Moral, R. Composting of animal manures and chemical criteria for compost maturity assessment: A review. Bioresour. Technol. 2009, 100, 5444–5453. [Google Scholar] [CrossRef]
- Penakalapati, G.; Swarthout, J.; Delahoy, M.J.; McAliley, L.; Wodnik, B.; Levy, K.; Freeman, M.C. Exposure to animal feces and human health: A systematic review and proposed research priorities. Environ. Sci. Technol. 2017, 51, 11537–11552. [Google Scholar] [CrossRef]
- Bryson, E.; Anastasi, A.; Bricknell, L.; Kift, R. Household dog fecal composting: Current issues and future directions. Integr. Environ. Assess. Manag. 2024, 20, 1876–1891. [Google Scholar] [CrossRef]
- Bryson, E.; Anastasi, A.; Bricknell, L.; Kift, R. What do Australians do with their dog poo? A survey of dog-owning household practices and attitudes. Australas. J. Environ. Manag. 2024, 31, 238–259. [Google Scholar] [CrossRef]
- Zhao, X.; Li, J.; Che, Z.; Xue, L. Succession of the bacterial communities and functional characteristics in sheep manure composting. Biology 2022, 11, 1181. [Google Scholar] [CrossRef] [PubMed]
- Yan, Z.-G.; Fan, J.-T.; Zheng, X.; Wang, S.-P.; Guo, X.-S.; Zhang, T.-X.; Yang, S.-W.; Zhang, Y.-Z. Neglect of temperature and pH impact leads to underestimation of seasonal ecological risk of ammonia in Chinese surface freshwaters. J. Chem. 2019, 2019, 3051398. [Google Scholar] [CrossRef]
- Fabian, C.; Reimann, C.; Fabian, K.; Birke, M.; Baritz, R.; Haslinger, E. GEMAS: Spatial distribution of the pH of European agricultural and grazing land soil. Appl. Geochem. 2014, 48, 207–216. [Google Scholar] [CrossRef]
- U.S. EPA. Understanding Global Warming Potentials. 2025. Available online: https://www.epa.gov/ghgemissions/understanding-global-warming-potentials (accessed on 25 September 2025).
- Yang, P.; Yu, M.; Ma, X.; Deng, D. Carbon Footprint of the Pork Product Chain and Recent Advancements in Mitigation Strategies. Foods 2023, 12, 4203. [Google Scholar] [CrossRef]
- Respect for Animals. Environment Report. November 2021. Available online: https://respectforanimals.org/wp-content/uploads/2021/11/ENVIRONMENT-REPORT-NOV-2021_FINAL_LO-RES_SINGLES.pdf (accessed on 26 October 2025).
- EMEP/EEA. Air Pollutant Emission Inventory Guidebook. 2023. Available online: https://www.eea.europa.eu/publications/emep-eea-guidebook-2023 (accessed on 25 September 2025).
- Verstraeten, W.W.; Boersma, K.F.; Douros, J.; Williams, J.E.; Eskes, H.; Liu, F.; Beirle, S.; Delcloo, A. Top-down NOx emissions of European cities based on the downwind plume of modelled and space-borne tropospheric NO2 columns. Sensors 2018, 18, 2893. [Google Scholar] [CrossRef] [PubMed]
- Nordahl, S.L.; Preble, C.V.; Kirchstetter, T.W.; Scown, C.D. Greenhouse gas and air pollutant emissions from composting. Environ. Sci. Technol. 2023, 57, 2235–2247. [Google Scholar] [CrossRef]
- Toro, M.V.; Cremades, L.V.; Calbó, J. Relationship between VOC and NOx emissions and chemical production of tropospheric ozone in the Aburrá Valley (Colombia). Chemosphere 2006, 65, 881–888. [Google Scholar] [CrossRef]
- Bateman, P.W.; Gilson, L.N. Bad dog? The environmental effects of owned dogs. Pac. Conserv. Biol. 2024, 31, PC24071. [Google Scholar] [CrossRef]
- Lee, J.M.; Tan, J.; Gill, A.S.; McGuire, K.L. Evaluating the effects of canine urine on urban soil microbial communities. Urban Ecosyst. 2019, 22, 721–732. [Google Scholar] [CrossRef]
- Backer, L.C.; Grindem, C.B.; Corbett, W.T.; Cullins, L.; Hunter, J.L. Pet dogs as sentinels for environmental contamination. Sci. Total Environ. 2001, 274, 161–169. [Google Scholar] [CrossRef] [PubMed]
- Mekonnen, M.M.; Hoekstra, A.Y. Global Anthropogenic Phosphorus Loads to Freshwater and Associated Grey Water Footprints and Water Pollution Levels: A High-Resolution Global Study. Water Resour. Res. 2017, 53, 2408–2422. [Google Scholar] [CrossRef]
- Hobbie, S.E.; Finlay, J.C.; Janke, B.D.; Nidzgorski, D.A.; Millet, D.B.; Baker, L.A. Contrasting nitrogen and phosphorus budgets in urban watersheds and implications for managing urban water pollution. Proc. Natl. Acad. Sci. USA 2017, 114, 4177–4182. [Google Scholar] [CrossRef] [PubMed]
- Smith, R.M.; Williamson, J.C.; Pataki, D.E.; Ehleringer, J.; Dennison, P. Soil carbon and nitrogen accumulation in residential lawns of the Salt Lake Valley, Utah. Oecologia 2018, 187, 1107–1118. [Google Scholar] [CrossRef]
- Blouin, D.D. Are Dogs Children, Companions, or Just Animals? Understanding variations in people’s orientations toward animals. Anthrozoös 2013, 26, 279–294. [Google Scholar] [CrossRef]
- Mai, L.; Zeng, E.; Zeng, E.Y. Dog poop bags: A non-negligible source of plastic pollution. Environ. Pollut. 2022, 292, 118355. [Google Scholar] [CrossRef]
- Buckley, J.; Druminski, D.; Halliday, A.; Lewis, A. Mechanical Properties and Degradation of Commercial Biodegradable Plastic Bags; Worcester Polytechnic Institute: Worcester, MA, USA, 2011. [Google Scholar]
- Dróżdż, D.; Malińska, K.; Postawa, P.; Stachowiak, T.; Nowak, D. End-of-life management of biodegradable plastic dog poop bags through composting of green waste. Materials 2022, 15, 2869. [Google Scholar] [CrossRef]
- Walker, T.R. What not to do with dog poop. Sci. Total Environ. 2023, 896, 165332. [Google Scholar] [CrossRef]
- Commission Regulation (EU). No 10/2011 of 14 January 2011 on Plastic Materials and Articles Intended to Come into Contact with Food. Available online: http://data.europa.eu/eli/reg/2011/10/2025-01-20 (accessed on 25 September 2025).
- Regulation (EU). 2025/40 of the European Parliament and of the Council of 19 December 2024 on Packaging and Packaging Waste. Available online: http://data.europa.eu/eli/reg/2025/40/oj (accessed on 25 September 2025).
- Lam, C.S.; Ramanathan, S.; Carbery, M.; Gray, K.; Vanka, K.S.; Maurin, C.; Bush, R.; Palanisami, T. A comprehensive analysis of plastics and microplastic legislation worldwide. Water Air Soil Pollut. 2018, 229, 345. [Google Scholar] [CrossRef]
- Pedrinelli, V.; Teixeira, F.A.; Queiroz, M.R.; Brunetto, M.A. Environmental impact of diets for dogs and cats. Sci. Rep. 2022, 12, 18510. [Google Scholar] [CrossRef]
- Gałęcki, R.; Pszczółkowski, B.; Zielonka, Ł. Experiences in Formulating Insect-Based Feeds: Selected Physicochemical Properties of Dog Food Containing Yellow Mealworm Meal. Animals 2025, 15, 2087. [Google Scholar] [CrossRef]
- Sieja, K.M.; Oba, P.M.; Applegate, C.C.; Pendlebury, C.; Kelly, J.; Swanson, K.S. Evaluation of high-protein diets differing in protein source in healthy adult dogs. J. Anim. Sci. 2023, 101, skad057. [Google Scholar] [CrossRef] [PubMed]
- Reilly, L.M.; von Schaumburg, P.C.; Hoke, J.M.; Davenport, G.M.; Utterback, P.L.; Parsons, C.M.; de Godoy, M.R.C. Use of the precision-fed cecectomized rooster assay to determine standardized amino acid digestibility, true metabolizable energy content, and digestible indispensable amino acid scores of plant-based protein by-products used in canine and feline diets. Transl. Anim. Sci. 2021, 5, txab025. [Google Scholar] [CrossRef]
- Triggs, A.; Bless, I.; Danner, L.; Saarela, M.; Wilkinson, K. Australian Dog Owners’ Acceptance of Insect-Based Pet Food. Insects 2025, 16, 290. [Google Scholar] [CrossRef] [PubMed]
- Kobayashi, R.; Nagaoka, K.; Nishimura, N.; Koike, S.; Takahashi, E.; Niimi, K.; Murase, H.; Kinjo, T.; Tsukahara, T.; Inoue, R. Comparison of the fecal microbiota of two monogastric herbivorous and five omnivorous mammals. Anim. Sci. J. 2020, 91, e13366. [Google Scholar] [CrossRef]
- Hossain, M.M.; Cho, S.B.; Kim, I.H. Strategies for reducing noxious gas emissions in pig production: A comprehensive review on the role of feed additives. J. Anim. Sci. Technol. 2024, 66, 237–250. [Google Scholar] [CrossRef] [PubMed]
- Philippe, F.-X.; Nicks, B. Review on greenhouse gas emissions from pig houses: Production of carbon dioxide, methane and nitrous oxide by animals and manure. Agric. Ecosyst. Environ. 2015, 199, 10–25. [Google Scholar] [CrossRef]
- He, Y.; Inamori, Y.; Mizuochi, M.; Kong, H.; Iwami, N.; Sun, T. Nitrous oxide emissions from aerated composting of organic waste. Environ. Sci. Technol. 2001, 35, 2347–2351. [Google Scholar] [CrossRef] [PubMed]
- Allen, J.A.; Setälä, H.; Kotze, D.J. Dog Urine Has Acute Impacts on Soil Chemistry in Urban Greenspaces. Front. Ecol. Evol. 2020, 8, 615979. [Google Scholar] [CrossRef]
| Species | Share of N2O (%) | N2O (Tg CO2-eq yr−1) | Reference |
|---|---|---|---|
| cattle | 12.90 | 494.05 | [35] |
| poultry | 20.20 | 115.59 | [35] |
| pig | 18.00 | 152.22 | [35] |
| American mink * | 47.00 | 13.16 kg | [36] |
| dog ** | 10.19 | 64.00 ± 16 | [5] |
Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |
© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Share and Cite
Krawczyk, A.; Nowakowicz-Dębek, B.; Chmielowiec-Korzeniowska, A.; Bis-Wencel, H. Environmental Pawprint of Dogs as a Contributor to Climate Change. Animals 2025, 15, 3152. https://doi.org/10.3390/ani15213152
Krawczyk A, Nowakowicz-Dębek B, Chmielowiec-Korzeniowska A, Bis-Wencel H. Environmental Pawprint of Dogs as a Contributor to Climate Change. Animals. 2025; 15(21):3152. https://doi.org/10.3390/ani15213152
Chicago/Turabian StyleKrawczyk, Antonina, Bożena Nowakowicz-Dębek, Anna Chmielowiec-Korzeniowska, and Hanna Bis-Wencel. 2025. "Environmental Pawprint of Dogs as a Contributor to Climate Change" Animals 15, no. 21: 3152. https://doi.org/10.3390/ani15213152
APA StyleKrawczyk, A., Nowakowicz-Dębek, B., Chmielowiec-Korzeniowska, A., & Bis-Wencel, H. (2025). Environmental Pawprint of Dogs as a Contributor to Climate Change. Animals, 15(21), 3152. https://doi.org/10.3390/ani15213152

