The Rosa alba L. and Rosa damascena Mill. growing in Bulgaria are known for their extremely fine essential oil and valuable hydrosols. Irrespectively of its wide use in human life, little research exists on the cytotoxic and genotoxic activity of the hydrosols. This set our goal to conduct cytogenetic analyses to study these effects. A complex of classical cytogenetic methods was applied in three types of experimental test systems—higher plant in vivo, ICR mice in vivo, and human lymphocytes in vitro. Mitotic index, PCE/(PCE + NCE) ratio, and nuclear division index were used as endpoints for cytotoxicity and for genotoxicity—induction of chromosome aberrations and micronuclei. Rose hydrosol treatments range in concentrations from 6% to 20%. It was obtained that both hydrosols did not show considerable cytotoxic and genotoxic effects. These effects depend on the type of the tested rose hydrosols, the concentrations applied in the experiments, and the sensitivity and specificity of the test systems used. Human lymphocytes in vitro were the most sensitive to hydrosols, followed by higher plant and animal cells. Chromosomal aberrations and micronucleus assays suggested that R. damascena and R. alba hydrosols at applied concentrations possess low genotoxic risk. Due to the overall low values in terms of cytotoxic and/or genotoxic effects in all test systems, hydrosols are promising for further use in various areas of human life.

The highly valued oil of Rosa damascena Mill. (Rosaceae), widely used in high perfumery, cosmetics, and other spheres of human life, obliges us to know and study the safety profile of the product obtained from the water–steam distillation of fresh rose petals. The genotoxicity of the essential oil (EsO) has not been thoroughly studied despite its wide range of applications. That predetermined the object of this study—to evaluate, through classical cytogenetic methods, the possible cytotoxic/genotoxic activities of R. damascena Mill. EsO (EsORdm) in three different test systems: plant root meristem cells, mammalian bone marrow cells, and human lymphocyte cultures. The rose essential oil showed varying concentration- and time-dependent cytotoxic and genotoxic effects depending on the test system used, and it was established that the oil showed moderate cytotoxicity in lymphocyte cultures and non-high cytotoxicity in ICR mice but none in barley. Both barley and human lymphocytes showed a genotoxic effect with a dose-dependent increase in chromosomal aberrations (CAs) and a substantial rise in micronucleus (MN) frequency, while no genotoxicity was observed in bone marrow cells at the applied concentrations. Human lymphocytes exhibited the highest susceptibility to cytotoxic and genotoxic actions of the EsO. As a valuable plant-derived aromatic product with versatile uses in human life, R. damascena Mill. essential oil should be used in an appropriate concentration range tailored to cellular sensitivity.

The possible clastogenic activity of tetrahydrofuran (THF), a synthetic organic substance, was explored employing two cytogenetic endpoints, i.e., chromosome aberrations (CA) and mitotic index (MI) analyses in vivo. The assays were carried out with ICR line laboratory mice as well as some widespread small mammal species in Bulgaria: yellow-necked wood mouse Apodemus flavicollis, mound-building mouse Mus spicilegus, bank voles Clethrionomys glareolus (= Myodes glareolus) and common vole Microtus arvalis. THF was introduced at 3.8 mg/kg b. w. (body weight) (0.01 mg/mL) by a single intraperitoneal (ip) administration. Cells with various structural CA were noted with significant (p < 0.01) differences in the frequencies of CA and MI between THF-treated groups and the negative control groups at dose or time interval used. The results of the present study reflect a positive in vivo clastogenic potential of THF.

The main object of this overview is to present our investigations on the safety assessment and some biological activities of the Rosa alba L. products (essential oil, hydrosol, and wastewater discarded during oil distillation) based on the results obtained on three types of test-systems: plant test-system, animal test-system in vivo, and human lymphocytes in vitro. The harmless use of such natural products is essential because of their important role in various spheres of human life - pharmacy, cosmetics, food industry, and others. For this purpose, the biological activity of the respective products must be determined. To obtain more detailed information about the specific effects of the products tested, a complex of cytogenetic tests was used, and various concentrations were tested, applying different experimental schemes. The results presented here, show that R. alba L. essential oil, its hydrosol, and wastewater did not possess high cytotoxic and genotoxic activities. These effects depended on the chemical components of each rose product, the concentrations applied, and the sensitivity of the test-system used. The tested rose products (essential oil and wastewater) have cytoprotective and genoprotective potential against the direct alkylating agent MNNG. Data are promising and show that these natural products are good candidates for further use in different sectors of human life.