The ratings of 7 Chemicals stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

International Flavors & Fragrances Inc.’s (IFF) rating weakens this week, dropping to a D versus last week’s C. International Flavors & Fragrances Inc. creates, manufactures, and supplies flavors and fragrances for the food, beverage, personal care and household products industries. For more information, get Portfolio Grader’s complete analysis of IFF stock.

Ashland Global Holdings, Inc. (ASH) declines this week from a C to a D. Ashland Global Holdings, Inc. is a global specialty chemicals company and provider of products, services, and solutions for a variety of industries. The company also gets F’s in earnings revisions, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of ASH stock.

Agrium Inc. (AGU) is having a tough week. The company’s rating falls from a C to a D. Agrium Inc. is a major retail supplier of agricultural products and services in the Americas, as well as a global producer and marketer of agricultural nutrients and industrial products. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings surprise, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of AGU stock.

A. Schulman, Inc. (SHLM) slips from a C to a D this week. A. Schulman, Inc. sells plastic resins and compounds, which are used as raw materials by its customers. The company also gets F’s in sales growth, operating margin growth, earnings growth, earnings momentum, and free cash flow. For more information, get Portfolio Grader’s complete analysis of SHLM stock.

Calgon Carbon Corporation (CCC) gets weaker ratings this week as last week’s C drops to a D. Calgon Carbon Corporation is engaged in products and services for purifying water and air. For more information, get Portfolio Grader’s complete analysis of CCC stock.

BioAmber, Inc. (BIOA) experiences a ratings drop this week, going from last week’s C to a D. The company also gets F’s in earnings surprise, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of BIOA stock.

This week, TerraVia Holdings, Inc.’s (TVIA) rating worsens to a F from the company’s D rating a week ago. The company also gets F’s in sales growth. For more information, get Portfolio Grader’s complete analysis of TVIA stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.