Higher doses can depress respiration and blood pressure. Fears that immigration would depress wages and raise unemployment rates were unfounded. As with other opiates, fentanyl can depress respiratory function. On the other hand, an excessive chlorination could depress excessively the activity of the catalyst. Raising taxes would depress fertility rates even further. At high vapor concentrations, it may depress the central nervous system like many other solvents. Smoking, alcoholism and drug abuse also depress immune response. Though he didn't impress with his action, he didn't depress either. However, larger or repeated doses can depress the baby. Commonly used sodium chloride can depress the freezing point of water to about . They argued that China had controls in place and the sale might depress prices. Giger's energy only seemed to depress her more. Frigid winds from the Himalayas can depress temperatures near the Brahmaputra River. The main guns of Soviet tanks could only depress 4 degrees. However, the heat did not depress the crew.