Photobiology Studies

Charles River established the first GLP-compliant, AAALAC-accredited contract photobiology facility in the industry, which has been meeting our clients’ phototoxicity testing needs since 1989. We serve the pharmaceutical, chemical and agrochemical industries with in vivo and in vitro study designs that meet standard and specialized requirements for evaluation of any test material.

Utilizing a number of different light sources, including visible light, xenon arc solar simulators, and fluorescent ultraviolet radiation sources, our scientists can design specialized exposure conditions and custom light source configurations for any product. We proudly offer the industry’s only FDA CFR Part 11-compliant radiometry and spectroradiometry systems. Their expertise in evaluating phototoxic responses is supported by other Charles River services, including pathology, pharmacokinetics, analytical and bioanalytical chemistry, clinical chemistry, quality assurance and report generation.

Phototoxicity Study Types

  • Cutaneous Phototoxicology

    Scientists at our Horsham site pioneered the quantitative study of cutaneous phototoxicology by designing the instruments, techniques, and protocols now accepted as industry standards for regulatory phototoxicity evaluations. We have used this strong foundation to develop unique and technologically rigorous phototoxicity testing services in collaboration with our research models experts and highly-skilled pathologists to support our clients’ research.

    We perform phototoxicology assays in mice, rats and guinea pigs, as well as photoallergy studies in guinea pigs. We also offer safety assessment studies to evaluate both photodynamic drugs and unique light sources. Dosing routes include oral, intravenous, dermal, intraocular, and ocular instillation, both single and multiple administrations.

  • Ocular Phototoxicology

    Charles River can assess the effects of exposure to visible light and ultraviolet radiation on ocular structures. Our study designs can include acute, continuous or interrupted light exposure, and we can perform slit lamp biomicroscopy, indirect ophthalmoscopy and tonometry. Our staff includes board-certified veterinary ophthalmologists and pathologists skilled in evaluating light-induced ophthalmic pathology.

  • Visceral Phototoxicology

    Our team can perform assessments of light exposure under surgical conditions using UVR, visible or near-infrared sources as well evaluate as the potential damage to thoracic and abdominal organs in rodents.

  • In Vitro Phototoxicology

    Charles River performs in vitro photosafety evaluations, primarily the OECD 432/ICH S10-compliant in vitro 3T3 neutral red uptake phototoxicity testing. Along with the 3T3 assay, we can perform the in vitro assessment of phototoxicity using 3D epidermal cell systems, the photomutagenicity assay, and the melanin binding assay. We will customize assays to undertake screening for large numbers of compounds for compound selection during development along with performing GLP-compliant assays.

Technical Capabilities

  • 6500w Xenon arc solar simulator
  • Fluorescent sources
  • Visible light sources, including operating room lights therapeutic lasers
  • Standard and unique light exposure conditions
  • Sponsor-provided light sources
  • Spectral distribution evaluation
  • Custom design of exposure systems
  • Custom light source configuration
  • Specific wavelength exposure protection
  • Spectral, dose and exposure condition characterization
  • Radiometry and spectroradiometry systems


​In Vitro and Alternative Models for Regulatory Submission

Dr. Clive Roper and Dr. Lauren Black were honored to contribute to the American College of Toxicology’s ToxChats© podcast series. In the first chapter of this episode, they discuss the current landscape of in vitro and alternative models and share their thoughts about the future direction of the field. In the second chapter, Dr. Paul Brown, associate director of pharmacology and toxicology at CDER/FDA, discusses the acceptance of in vitro models for safety evaluations and the value of integrative toxicology. Listen Now