*4.3. IPCC*

The consumption of non-renewable fuels throughout the car tire use period is inherent in the emission of greenhouse gases in the atmosphere. In fact, any action to reduce the pollution rates will be considered positive from the perspective of climate protection. Fitting cars with environmentally friendly tires could potentially reduce harmful emissions by 119 kg CO2eq compared to traditional tires (Figure 12). However, it would be the replacement of conventional fuels that power cars with renewable energy sources that would be sure to reduce the extent of the environmental burden throughout the life cycle of both conventional and green tires.

**Figure 12.** Intergovernmental Panel on Climate Change (IPCC) assessment of greenhouse gas (GHG) emissions at individual stages of the traditional and ecological tire life cycle.

#### **5. Summary and Conclusions**

Tire manufacturing is a complex process with a multiple-stage execution. Manufacturers follow in-house production standards and procedures, which explicitly specify the entire process from the acquisition of raw resources to quality management. Faulty quality control could contribute to the emergence of hidden defects in both material quality and dimensional and shape accuracy. While the defects may be visible in a tire at purchase, they could also emerge in use, thereby contributing to the deterioration of operating conditions and travel comfort [52,53].

Manufacturing activities have a significant (usually negative) impact on the environment, including due to the consumption of natural resources, emissions of harmful substances, and the generation of waste. The level of air quality is significantly lower, generating many threats to human health. Air pollution associated with the production of car tires is a serious health risk because it shortens life expectancy and contributes to the occurrence of many diseases, including heart disease, respiratory disease, and cancer. Inhaling air with a high content of harmful substances not only causes health problems of varying severity but can even cause death in the long term.

The aim of the work was achieved owing to the use of LCA as an effective tool for the environmental production of car tires made in a traditional and ecological manner. The conducted research shows that a tire made in accordance with the traditional technology generates more negative consequences for the environment compared to an ecological tire. This is due to a larger (by about 20%) amount of materials used in its production. The most harmful environmental impact at the manufacturing stage is due to the high level of consumption of the constantly depleting natural resources that are necessary in the manufacturing process of car tires. The extraction of fossil fuels is an important cause of environmental degradation and deterioration of human health.

As it results from the analyses, the key factor generating the most negative environmental consequences (apart from manufacturing) is the operation stage. The use of unconventional, renewable energy sources to power a passenger car could significantly contribute to reducing the negative impact on the environment (e.g., by reducing the impact of fossil fuel extraction and the processes of obtaining energy from them).

Considering the economies of scale, i.e., the number of passenger cars registered in Europe, the use of environmentally friendly (lighter weight) tires would save a large amount of material resources needed at the manufacturing stage. This would translate, in a broader perspective, into the improvement of the environment. The possibility of obtaining conventional energy resources is

becoming more difficult and more limited. The extraction of coal and crude oil and their combustion, in addition to the negative impact on the greenhouse effect and air purity, also causes irreversible damage to the landscape, land, and disturbances in the management of groundwater and ecosystems.

The results of the conducted research show that the processes related to the extraction of fossil fuels and emissions of inorganic compounds causing respiratory diseases, but also emissions of compounds causing climate change, compounds causing acidification/eutrophication, and carcinogens cause the most negative environmental consequences.

However, it is possible to control the production process of car tires in such a way as to limit its negative impact on the environment. For this purpose, it is possible to:


**Author Contributions:** Conceptualization, P.K. and P.I.; methodology, P.K., P.I., B.-W.P., K.W. and T.A.; software, P.K., P.I., B.-W.P. and K.W.; validation, P.I. and B.-W.P.; formal analysis, P.K., B.-W.P. and K.W.; investigation P.I., B.-W.P., K.W. and T.A.; resources, P.K. and P.I.; data curation, P.I., B.-W.P. and T.A.; writing—original draft preparation, P.K., P.I.; writing—review and editing, P.K., B.-W.P., and T.A.; visualization, P.I., B.-W.P. and K.W.; supervision, P.K., P.I., and T.A.; project administration, P.K. and P.I. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The authors declare no conflict of interest.
