A disposable fluid processing set (200, 240) for use in a photoactivation treatment of a blood product comprising: a. a first container (202, 242) with a photochemical agent contained therein, said container (202, 242)being adapted for joinder to a source container of blood product said first container including a light impermeable overwrap to protect the photochemical agent from exposure to light of a wavelength which could result in premature activation of the photochemical agent; b. a second container (206, 244) downstream of and integrally interconnected with a tubing segment (205, 243) to said first container (202, 242) for holding the blood product and the photochemical agent during a photoactivation treatment, wherein said second container (206, 244) is made of a material that is translucent to light in the photoactivating wavelength range; c. said tubing segment (205, 243) between said first (202, 242) and said second containers (206, 244) defines a sealed but openable flow path; d. a third container (210, 246) comprising adsorbent material for removing at least one of excess photochemical agent and photoactivation by-products from said blood product and being downstream of and integrally interconnected with a tubing segment (208, 245) to said second container (206, 244) for contacting at least said blood product from said second container (206, 244) with the said adsorbent material; e. said tubing segment (208, 245) between said second container (206, 244) and said third container (210, 246) defines a sealed but openable flow paht; f. a storage container (214, 248) downstream of and integrally interconnected by a tubing segment (211, 247) to said third container (210, 246) for receiving said blood product from said third container (210, 246). a. a first container (202, 242) with a photochemical agent contained therein, said container (202, 242)being adapted for joinder to a source container of blood product said first container including a light impermeable overwrap to protect the photochemical agent from exposure to light of a wavelength which could result in premature activation of the photochemical agent; b. a second container (206, 244) downstream of and integrally interconnected with a tubing segment (205, 243) to said first container (202, 242) for holding the blood product and the photochemical agent during a photoactivation treatment, wherein said second container (206, 244) is made of a material that is translucent to light in the photoactivating wavelength range; c. said tubing segment (205, 243) between said first (202, 242) and said second containers (206, 244) defines a sealed but openable flow path; d. a third container (210, 246) comprising adsorbent material for removing at least one of excess photochemical agent and photoactivation by-products from said blood product and being downstream of and integrally interconnected with a tubing segment (208, 245) to said second container (206, 244) for contacting at least said blood product from said second container (206, 244) with the said adsorbent material; e. said tubing segment (208, 245) between said second container (206, 244) and said third container (210, 246) defines a sealed but openable flow paht; f. a storage container (214, 248) downstream of and integrally interconnected by a tubing segment (211, 247) to said third container (210, 246) for receiving said blood product from said third container (210, 246).