The phrase "are substantial challenges to" is correct and usable in written English.
It can be used when discussing significant difficulties or obstacles that affect a particular situation, issue, or subject.
Example: "There are substantial challenges to implementing the new policy effectively across all departments."
Alternatives: "pose significant challenges to" or "represent major obstacles to".
Hydrogen is considered a sort of holy grail of fuel, but there are substantial challenges to its development.
Fear of exploitation (Snow, 2012) and contradicting objectives (Miles et al., 2010) are substantial challenges to a productive and effective collaborative design, which unfortunately is a part of the Greenlandic businesses' experience with collaboration.
Nevertheless, there are substantial challenges to achieving the family planning benchmark in many countries.
In a multi-ethnic population with variable levels of education there are substantial challenges to obtaining an informed consent or developing an effective therapeutic relationship with patients.
Despite impressive growth in the first year of operations, Mr. Fils-Aime said there were substantial challenges to operating a wireless carrier in Haiti.
However, there are substantial challenges with the pharmacokinetics of rapamycin due to its lipophilic chemistry [32].
There are substantial challenges in designing such a vehicle, which appears to have been one of the factors that drew Reitz towards the project.
What all these companies share, industry analysts say, are substantial challenges in making rich, colorful Web content easy to read and navigate on mobile devices, which are hampered by small screens, slow speeds for gaining access to data and limited battery life.
There are substantial challenges ahead, from data protection alignment between countries and companies, to London potentially losing the right to clear euro-denominated securities – a disaster for money transfer firms.
However, as there are substantial challenges in reliably measuring adherence, the study is powered to detect meaningful differences in the biological proxies of blood pressure and total cholesterol levels.
These high-throughput data sets are not amenable to standard phylogenetic analysis, as there are substantial challenges for computing, evaluating, and visualizing alignments and phylogenies for such large data sets.
