Corrosion and wear products are HUGE considerations for both primary and secondary at a PWR. Here's some non-radiological considerations.
On the primary side, especially in larger cores, for example, nickel ferrite tends to deposit on the core which in turn can cause boron precipitates to form in hot regions. This eventually leads to uneven power production across the core axially (axial offset anomaly), and can cause power production in the top and the bottom of the core to become uncoupled when manuevering power (xenon). These have been controlled largely by having to redesign cores and change the chemistry at temperature pH and lithium concentrations.
Iron and copper deposition in the secondary wreak havoc on Alloy 600 tubes, and we'll see for new SG replacements for alloy 690.
While not in tech specs, controls are usually specified by endorsement of EPRI guidance in the plant updated FSAR, which is controlled by the facility operating license. So it is regulated. The NRC doesn't pay a whole lot of attention to these unless you start having problems that you can't seem to fix. INPO, on the other hand, spends a lot of time in the area and numbers are reported for their performance indicators.
Hope this helps.