blessman explained, "federal limits are one parts per million, which is very easy to meet with copper alloy tubes." but he added, "localized limits, mostly state driven, could be much more stringent."

Write the above sentence using proper case.
Blessman explained, "Federal limits are one parts per million, which is very easy to meet with copper alloy tubes." But he added, "Localized limits, mostly state driven, could be much more stringent."