You can help latex by supplying possible hyphenation points with \- (disclaimer: I don't know what the correct hyphenations points in Epibrdrinharzechlor are, the following is just a proof-of-concept to see that hyphenation works):

\documentclass[10pt]{article}

\usepackage[top=2cm, bottom=4cm, left=1.5cm, right=1.7cm]{geometry}
\usepackage{tabularray}
\UseTblrLibrary{booktabs}

\begin{document}

\noindent
\begin{tblr}{
  colspec={XXXXXXXXXX},
  colsep=2pt,
  cells={halign=l,preto=\hspace*{0pt}}
}
\toprule\toprule
Name & Substance & Material & Separable & Share & Type & Classification & Documentation & Threshold &  Fraction\\\hline
\midrule
20- Res & Berovi\-werx-Epibr\-drin\-harze\-chlor & Alsternative Test inside the modular &  &  &  & Ski1 &  & 0.01 & 200.0\\\hline
\bottomrule
\end{tblr}
\end{document}