Flame retardants (FRs) that have an adverse effect on human and the environment have been subject to regulation since 1972. However, FRs emerging as a replacement, are not proving to be fully environmentally safe. Water and sediment contamination by FRs, including organophosphorus (OPFRs) and novel brominated (NBFRs) ones, is a matter of major concern. Due to their common usage, many release sources, and relatively high mobility, they pose a threat to aquatic organisms and ecosystems. This review summarises studies on the OPFRs’, and NBFRs’ simultaneous occurrence in water and corresponding sediment. The main sources of occurrence and routes of entry of FRs into the environment are presented. The newest reports on the ecotoxicity of selected FRs had been summarised in order to bring the matter to attention. The research revealed that although great efforts had been made to study the occurrence of OPFRs and NBFRs in water and sediment separately, there is a lack of research on their occurrence in both media in the same area. Although major efforts have been made to study the ecotoxicity of OPFRs, there are some deficiencies for the NBFRs. Considering their relatively high ecotoxicity, further studies should be conducted on joint ecotoxicity, which may cause synergistic or antagonistic effects.

The antilock brake system (ABS) was developed, which coordinates actions of auxiliary and working braking systems of a trolleybus. A trolleybus type 321 "Belkommunmash", equipped with the proposed ABS was tested in road conditions. The results of tests confirmed compliance of the trolleybus with requirements of the rules UN EEC No 13. Decrease in slippage of the driving wheels, improved stability, roadability and traffic safety of the trolleybus was noted.

Levels and distribution of selected polybrorninated diphenyl ether congeners in dust samples taken from different indoor environments in Lublin, South-Eastern Poland, are reported. The most abundant congeners, found in the majority of sampling sites, were BOE 47, 100 and 28, respectively. The highest levels of examined congeners were observed in dust samples taken from a computer repair facility and labs. BOE 47, 99 and 100, occurring at highest levels and having the greatest contribution confirm that in Polish indoor environments polymer products contain Penta - BOE technical mixture.

Thanks to dyeing of polymers, the possibilities of their use are constantly increasing. It is equally important to use additives that will have several functions. A perfect example is titanium dioxide used as an optical brightener and a flame retardant at the same time. Mostly it is used in the form of a powder. However, there are no studies where TiO2 is used as a colourbatch based on the different polymer matrix.
The aim of the work was to investigate the effect of titanium white in the form of colourbatch on the flammability and selected properties of mouldings produced in various processing conditions. Colourbatch based on PS matrix, was used in the research. The variable processing parameters were: injection temperature Tw, volume flow rate Vw, residence time and the addition of a colourbatch. On the basis of the measurements, it was found that the processing conditions and the addition of the colourbatch have low effect on the hardness of the mouldings, which was in the range from 75.59o Sh D (Shore type D) to 81.95o Sh D. It was also noted that the addition of colourbatch with TiO2 and increasing injection temperature reduces impact strength even by several dozen percent. Moreover, it was found that use of TiO2 causes a delay in the ignitability of the samples in selected cases. It is difficult to determine whether the variable processing conditions or the addition of TiO2 on the PS matrix have a greater impact on the ignitability of the moulded parts.

We investigate a scalar characteristic exponential polynomial with complex coefficients associated with a first order scalar differential-difference equation. Our analysis provides necessary and sufficient conditions for allocation of the roots in the complex open left half-plane what guarantees asymptotic stability of the differential-difference equation. The conditions are expressed explicitly in terms of complex coefficients of the characteristic exponential polynomial, what makes them easy to use in applications. We show examples including those for retarded PDEs in an abstract formulation.